This section summarizes what has been added to, deprecated in, and removed from MySQL 5.7. A companion section lists MySQL server options and variables that have been added, deprecated, or removed in MySQL 5.7; see Section 1.4, “Server and Status Variables and Options Added, Deprecated, or Removed in MySQL 5.7”.
The following features have been added to MySQL 5.7:
Security improvements. These security enhancements were added:
In MySQL 8.0,
caching_sha2_password
is the default authentication plugin. To enable MySQL 5.7 clients to connect to 8.0 servers using accounts that authenticate usingcaching_sha2_password
, the MySQL 5.7 client library and client programs support thecaching_sha2_password
client-side authentication plugin as of MySQL 5.7.23. This improves compatibility of MySQL 5.7 with MySQL 8.0 and higher servers. See Section 6.4.1.4, “Caching SHA-2 Pluggable Authentication”.The server now requires account rows in the
mysql.user
system table to have a nonemptyplugin
column value and disables accounts with an empty value. For server upgrade instructions, see Section 2.10.3, “Changes in MySQL 5.7”. DBAs are advised to also convert accounts that use themysql_old_password
authentication plugin to usemysql_native_password
instead, because support formysql_old_password
has been removed. For account upgrade instructions, see Section 6.4.1.3, “Migrating Away from Pre-4.1 Password Hashing and the mysql_old_password Plugin”.MySQL now enables database administrators to establish a policy for automatic password expiration: Any user who connects to the server using an account for which the password is past its permitted lifetime must change the password. For more information, see Section 6.2.11, “Password Management”.
Administrators can lock and unlock accounts for better control over who can log in. For more information, see Section 6.2.15, “Account Locking”.
To make it easier to support secure connections, MySQL servers compiled using OpenSSL can automatically generate missing SSL and RSA certificate and key files at startup. See Section 6.3.3.1, “Creating SSL and RSA Certificates and Keys using MySQL”.
All servers, if not configured for SSL explicitly, attempt to enable SSL automatically at startup if they find the requisite SSL files in the data directory. See Section 6.3.1, “Configuring MySQL to Use Encrypted Connections”.
In addition, MySQL distributions include a mysql_ssl_rsa_setup utility that can be invoked manually to create SSL and RSA key and certificate files. For more information, see Section 4.4.5, “mysql_ssl_rsa_setup — Create SSL/RSA Files”.
MySQL deployments installed using mysqld --initialize are secure by default. The following changes have been implemented as the default deployment characteristics:
The installation process creates only a single
root
account,'root'@'localhost'
, automatically generates a random password for this account, and marks the password expired. The MySQL administrator must connect asroot
using the random password and assign a new password. (The server writes the random password to the error log.)Installation creates no anonymous-user accounts.
Installation creates no
test
database.
For more information, see Section 2.9.1, “Initializing the Data Directory”.
MySQL Enterprise Edition now provides data masking and de-identification capabilities. Data masking hides sensitive information by replacing real values with substitutes. MySQL Enterprise Data Masking and De-Identification functions enable masking existing data using several methods such as obfuscation (removing identifying characteristics), generation of formatted random data, and data replacement or substitution. For more information, see Section 6.5, “MySQL Enterprise Data Masking and De-Identification”.
MySQL now sets the access control granted to clients on the named pipe to the minimum necessary for successful communication on Windows. Newer MySQL client software can open named pipe connections without any additional configuration. If older client software cannot be upgraded immediately, the new
named_pipe_full_access_group
system variable can be used to give a Windows group the necessary permissions to open a named pipe connection. Membership in the full-access group should be restricted and temporary.
SQL mode changes. Strict SQL mode for transactional storage engines (
STRICT_TRANS_TABLES
) is now enabled by default.Implementation for the
ONLY_FULL_GROUP_BY
SQL mode has been made more sophisticated, to no longer reject deterministic queries that previously were rejected. In consequence, this mode is now enabled by default, to prohibit only nondeterministic queries containing expressions not guaranteed to be uniquely determined within a group.The
ERROR_FOR_DIVISION_BY_ZERO
,NO_ZERO_DATE
, andNO_ZERO_IN_DATE
SQL modes are now deprecated but enabled by default. The long term plan is to have them included in strict SQL mode and to remove them as explicit modes in a future MySQL release. See SQL Mode Changes in MySQL 5.7.The changes to the default SQL mode result in a default
sql_mode
system variable value with these modes enabled:ONLY_FULL_GROUP_BY
,STRICT_TRANS_TABLES
,NO_ZERO_IN_DATE
,NO_ZERO_DATE
,ERROR_FOR_DIVISION_BY_ZERO
,NO_AUTO_CREATE_USER
, andNO_ENGINE_SUBSTITUTION
.Online ALTER TABLE.
ALTER TABLE
now supports aRENAME INDEX
clause that renames an index. The change is made in place without a table-copy operation. It works for all storage engines. See Section 13.1.8, “ALTER TABLE Statement”.ngram and MeCab full-text parser plugins. MySQL provides a built-in full-text ngram parser plugin that supports Chinese, Japanese, and Korean (CJK), and an installable MeCab full-text parser plugin for Japanese.
For more information, see Section 12.9.8, “ngram Full-Text Parser”, and Section 12.9.9, “MeCab Full-Text Parser Plugin”.
InnoDB enhancements. These
InnoDB
enhancements were added:VARCHAR
column size can be increased using an in-placeALTER TABLE
, as in this example:ALTER TABLE t1 ALGORITHM=INPLACE, CHANGE COLUMN c1 c1 VARCHAR(255);
This is true as long as the number of length bytes required by a
VARCHAR
column remains the same. ForVARCHAR
columns of 0 to 255 bytes in size, one length byte is required to encode the value. ForVARCHAR
columns of 256 bytes in size or more, two length bytes are required. As a result, in-placeALTER TABLE
only supports increasingVARCHAR
column size from 0 to 255 bytes, or from 256 bytes to a greater size. In-placeALTER TABLE
does not support increasing the size of aVARCHAR
column from less than 256 bytes to a size equal to or greater than 256 bytes. In this case, the number of required length bytes changes from 1 to 2, which is only supported by a table copy (ALGORITHM=COPY
).Decreasing
VARCHAR
size using in-placeALTER TABLE
is not supported. DecreasingVARCHAR
size requires a table copy (ALGORITHM=COPY
).For more information, see Section 14.13.1, “Online DDL Operations”.
DDL performance for
InnoDB
temporary tables is improved through optimization ofCREATE TABLE
,DROP TABLE
,TRUNCATE TABLE
, andALTER TABLE
statements.InnoDB
temporary table metadata is no longer stored toInnoDB
system tables. Instead, a new table,INNODB_TEMP_TABLE_INFO
, provides users with a snapshot of active temporary tables. The table contains metadata and reports on all user and system-created temporary tables that are active within a givenInnoDB
instance. The table is created when the firstSELECT
statement is run against it.InnoDB
now supports MySQL-supported spatial data types. Prior to this release,InnoDB
would store spatial data as binaryBLOB
data.BLOB
remains the underlying data type but spatial data types are now mapped to a newInnoDB
internal data type,DATA_GEOMETRY
.There is now a separate tablespace for all non-compressed
InnoDB
temporary tables. The new tablespace is always recreated on server startup and is located inDATADIR
by default. A newly added configuration file option,innodb_temp_data_file_path
, allows for a user-defined temporary data file path.innochecksum functionality is enhanced with several new options and extended capabilities. See Section 4.6.1, “innochecksum — Offline InnoDB File Checksum Utility”.
A new type of non-redo undo log for both normal and compressed temporary tables and related objects now resides in the temporary tablespace. For more information, see Section 14.6.7, “Undo Logs”.
InnoDB
buffer pool dump and load operations are enhanced. A new system variable,innodb_buffer_pool_dump_pct
, allows you to specify the percentage of most recently used pages in each buffer pool to read out and dump. When there is other I/O activity being performed byInnoDB
background tasks,InnoDB
attempts to limit the number of buffer pool load operations per second using theinnodb_io_capacity
setting.Support is added to
InnoDB
for full-text parser plugins. For information about full-text parser plugins, see Full-Text Parser Plugins and Writing Full-Text Parser Plugins.InnoDB
supports multiple page cleaner threads for flushing dirty pages from buffer pool instances. A new system variable,innodb_page_cleaners
, is used to specify the number of page cleaner threads. The default value of1
maintains the previous configuration in which there is a single page cleaner thread. This enhancement builds on work completed in MySQL 5.6, which introduced a single page cleaner thread to offload buffer pool flushing work from theInnoDB
master thread.Online DDL support is extended to the following operations for regular and partitioned
InnoDB
tables:ALTER TABLE ... ENGINE=INNODB
(when run on anInnoDB
table)Online DDL support reduces table rebuild time and permits concurrent DML. See Section 14.13, “InnoDB and Online DDL”.
The Fusion-io Non-Volatile Memory (NVM) file system on Linux provides atomic write capability, which makes the
InnoDB
doublewrite buffer redundant. TheInnoDB
doublewrite buffer is automatically disabled for system tablespace files (ibdata files) located on Fusion-io devices that support atomic writes.InnoDB
supports the Transportable Tablespace feature for partitionedInnoDB
tables and individualInnoDB
table partitions. This enhancement eases backup procedures for partitioned tables and enables copying of partitioned tables and individual table partitions between MySQL instances. For more information, see Section 14.6.1.3, “Importing InnoDB Tables”.The
innodb_buffer_pool_size
parameter is dynamic, allowing you to resize the buffer pool without restarting the server. The resizing operation, which involves moving pages to a new location in memory, is performed in chunks. Chunk size is configurable using the newinnodb_buffer_pool_chunk_size
configuration option. You can monitor resizing progress using the newInnodb_buffer_pool_resize_status
status variable. For more information, see Configuring InnoDB Buffer Pool Size Online.Multithreaded page cleaner support (
innodb_page_cleaners
) is extended to shutdown and recovery phases.InnoDB
supports indexing of spatial data types usingSPATIAL
indexes, including use ofALTER TABLE ... ALGORITHM=INPLACE
for online operations (ADD SPATIAL INDEX
).InnoDB
performs a bulk load when creating or rebuilding indexes. This method of index creation is known as a “sorted index build”. This enhancement, which improves the efficiency of index creation, also applies to full-text indexes. A new global configuration option,innodb_fill_factor
, defines the percentage of space on each page that is filled with data during a sorted index build, with the remaining space reserved for future index growth. For more information, see Section 14.6.2.3, “Sorted Index Builds”.A new log record type (
MLOG_FILE_NAME
) is used to identify tablespaces that have been modified since the last checkpoint. This enhancement simplifies tablespace discovery during crash recovery and eliminates scans on the file system prior to redo log application. For more information about the benefits of this enhancement, see Tablespace Discovery During Crash Recovery.This enhancement changes the redo log format, requiring that MySQL be shut down cleanly before upgrading to or downgrading from MySQL 5.7.5.
You can truncate undo logs that reside in undo tablespaces. This feature is enabled using the
innodb_undo_log_truncate
configuration option. For more information, see Truncating Undo Tablespaces.InnoDB
supports native partitioning. Previously,InnoDB
relied on theha_partition
handler, which creates a handler object for each partition. With native partitioning, a partitionedInnoDB
table uses a single partition-aware handler object. This enhancement reduces the amount of memory required for partitionedInnoDB
tables.As of MySQL 5.7.9, mysql_upgrade looks for and attempts to upgrade partitioned
InnoDB
tables that were created using theha_partition
handler. Also in MySQL 5.7.9 and later, you can upgrade such tables by name in the mysql client usingALTER TABLE ... UPGRADE PARTITIONING
.InnoDB
supports the creation of general tablespaces usingCREATE TABLESPACE
syntax.CREATE TABLESPACE `tablespace_name` ADD DATAFILE 'file_name.ibd' [FILE_BLOCK_SIZE = n]
General tablespaces can be created outside of the MySQL data directory, are capable of holding multiple tables, and support tables of all row formats.
Tables are added to a general tablespace using
CREATE TABLE
ortbl_name
... TABLESPACE [=]tablespace_name
ALTER TABLE
syntax.tbl_name
TABLESPACE [=]tablespace_name
For more information, see Section 14.6.3.3, “General Tablespaces”.
DYNAMIC
replacesCOMPACT
as the implicit default row format forInnoDB
tables. A new configuration option,innodb_default_row_format
, specifies the defaultInnoDB
row format. For more information, see Defining the Row Format of a Table.As of MySQL 5.7.11,
InnoDB
supports data-at-rest encryption for file-per-table tablespaces. Encryption is enabled by specifying theENCRYPTION
option when creating or altering anInnoDB
table. This feature relies on akeyring
plugin for encryption key management. For more information, see Section 6.4.4, “The MySQL Keyring”, and Section 14.14, “InnoDB Data-at-Rest Encryption”.As of MySQL 5.7.24, the zlib library version bundled with MySQL was raised from version 1.2.3 to version 1.2.11. MySQL implements compression with the help of the zlib library.
If you use
InnoDB
compressed tables, see Section 2.10.3, “Changes in MySQL 5.7” for related upgrade implications.
JSON support. Beginning with MySQL 5.7.8, MySQL supports a native
JSON
type. JSON values are not stored as strings, instead using an internal binary format that permits quick read access to document elements. JSON documents stored inJSON
columns are automatically validated whenever they are inserted or updated, with an invalid document producing an error. JSON documents are normalized on creation, and can be compared using most comparison operators such as=
,<
,<=
,>
,>=
,<>
,!=
, and<=>
; for information about supported operators as well as precedence and other rules that MySQL follows when comparingJSON
values, see Comparison and Ordering of JSON Values.MySQL 5.7.8 also introduces a number of functions for working with
JSON
values. These functions include those listed here:Functions that create
JSON
values:JSON_ARRAY()
,JSON_MERGE()
, andJSON_OBJECT()
. See Section 12.17.2, “Functions That Create JSON Values”.Functions that search
JSON
values:JSON_CONTAINS()
,JSON_CONTAINS_PATH()
,JSON_EXTRACT()
,JSON_KEYS()
, andJSON_SEARCH()
. See Section 12.17.3, “Functions That Search JSON Values”.Functions that modify
JSON
values:JSON_APPEND()
,JSON_ARRAY_APPEND()
,JSON_ARRAY_INSERT()
,JSON_INSERT()
,JSON_QUOTE()
,JSON_REMOVE()
,JSON_REPLACE()
,JSON_SET()
, andJSON_UNQUOTE()
. See Section 12.17.4, “Functions That Modify JSON Values”.Functions that provide information about
JSON
values:JSON_DEPTH()
,JSON_LENGTH()
,JSON_TYPE()
, andJSON_VALID()
. See Section 12.17.5, “Functions That Return JSON Value Attributes”.
In MySQL 5.7.9 and later, you can use
as shorthand forcolumn
->path
JSON_EXTRACT(
. This works as an alias for a column wherever a column identifier can occur in an SQL statement, includingcolumn
,path
)WHERE
,ORDER BY
, andGROUP BY
clauses. This includesSELECT
,UPDATE
,DELETE
,CREATE TABLE
, and other SQL statements. The left hand side must be aJSON
column identifier (and not an alias). The right hand side is a quoted JSON path expression which is evaluated against the JSON document returned as the column value.MySQL 5.7.22 adds the following JSON functions:
Two JSON aggregation functions
JSON_ARRAYAGG()
andJSON_OBJECTAGG()
.JSON_ARRAYAGG()
takes a column or expression as its argument, and aggregates the result as a singleJSON
array. The expression can evaluate to any MySQL data type; this does not have to be aJSON
value.JSON_OBJECTAGG()
takes two columns or expressions which it interprets as a key and a value; it returns the result as a singleJSON
object. For more information and examples, see Section 12.19, “Aggregate Functions”.The JSON utility function
JSON_PRETTY()
, which outputs an existingJSON
value in an easy-to-read format; each JSON object member or array value is printed on a separate line, and a child object or array is intended 2 spaces with respect to its parent.This function also works with a string that can be parsed as a JSON value.
The JSON utility function
JSON_STORAGE_SIZE()
, which returns the storage space in bytes used for the binary representation of a JSON document prior to any partial update (see previous item).This function also accepts a valid string representation of a JSON document. For such a value,
JSON_STORAGE_SIZE()
returns the space used by its binary representation following its conversion to a JSON document. For a variable containing the string representation of a JSON document,JSON_STORAGE_FREE()
returns zero. Either function produces an error if its (non-null) argument cannot be parsed as a valid JSON document, andNULL
if the argument isNULL
.For more information and examples, see Section 12.17.6, “JSON Utility Functions”.
A JSON merge function intended to conform to RFC 7396.
JSON_MERGE_PATCH()
, when used on 2 JSON objects, merges them into a single JSON object that has as members a union of the following sets:Each member of the first object for which there is no member with the same key in the second object.
Each member of the second object for which there is no member having the same key in the first object, and whose value is not the JSON
null
literal.Each member having a key that exists in both objects, and whose value in the second object is not the JSON
null
literal.
As part of this work, the
JSON_MERGE()
function has been renamedJSON_MERGE_PRESERVE()
.JSON_MERGE()
continues to be recognized as an alias forJSON_MERGE_PRESERVE()
in MySQL 5.7, but is now deprecated and is subject to removal in a future version of MySQL.For more information and examples, see Section 12.17.4, “Functions That Modify JSON Values”.
See Section 12.17.3, “Functions That Search JSON Values”, for more information about
->
andJSON_EXTRACT()
. For information about JSON path support in MySQL 5.7, see Searching and Modifying JSON Values. See also Indexing a Generated Column to Provide a JSON Column Index.System and status variables. System and status variable information is now available in Performance Schema tables, in preference to use of
INFORMATION_SCHEMA
tables to obtain these variable. This also affects the operation of theSHOW VARIABLES
andSHOW STATUS
statements. The value of theshow_compatibility_56
system variable affects the output produced from and privileges required for system and status variable statements and tables. For details, see the description of that variable in Section 5.1.7, “Server System Variables”.NoteThe default for
show_compatibility_56
isOFF
. Applications that require 5.6 behavior should set this variable toON
until such time as they have been migrated to the new behavior for system variables and status variables. See Section 25.20, “Migrating to Performance Schema System and Status Variable Tables”sys schema. MySQL distributions now include the
sys
schema, which is a set of objects that help DBAs and developers interpret data collected by the Performance Schema.sys
schema objects can be used for typical tuning and diagnosis use cases. For more information, see Chapter 26, MySQL sys Schema.Condition handling. MySQL now supports stacked diagnostics areas. When the diagnostics area stack is pushed, the first (current) diagnostics area becomes the second (stacked) diagnostics area and a new current diagnostics area is created as a copy of it. Within a condition handler, executed statements modify the new current diagnostics area, but
GET STACKED DIAGNOSTICS
can be used to inspect the stacked diagnostics area to obtain information about the condition that caused the handler to activate, independent of current conditions within the handler itself. (Previously, there was a single diagnostics area. To inspect handler-activating conditions within a handler, it was necessary to check this diagnostics area before executing any statements that could change it.) See Section 13.6.7.3, “GET DIAGNOSTICS Statement”, and Section 13.6.7.7, “The MySQL Diagnostics Area”.Optimizer. These optimizer enhancements were added:
EXPLAIN
can be used to obtain the execution plan for an explainable statement executing in a named connection:EXPLAIN [options] FOR CONNECTION connection_id;
For more information, see Section 8.8.4, “Obtaining Execution Plan Information for a Named Connection”.
It is possible to provide hints to the optimizer within individual SQL statements, which enables finer control over statement execution plans than can be achieved using the
optimizer_switch
system variable. Hints are also permitted in statements used withEXPLAIN
, enabling you to see how hints affect execution plans. For more information, see Section 8.9.3, “Optimizer Hints”.prefer_ordering_index flag. By default, MySQL attempts to use an ordered index for any
ORDER BY
orGROUP BY
query that has aLIMIT
clause, whenever the optimizer determines that this would result in faster execution. Because it is possible in some cases that choosing a different optimization for such queries actually performs better, it is possible as of MySQL 5.7.33 to disable this optimization by setting theprefer_ordering_index
flag tooff
.The default value for this flag is
on
.For more information and examples, see Section 8.9.2, “Switchable Optimizations”, and Section 8.2.1.17, “LIMIT Query Optimization”.
Triggers. Previously, a table could have at most one trigger for each combination of trigger event (
INSERT
,UPDATE
,DELETE
) and action time (BEFORE
,AFTER
). This limitation has been lifted and multiple triggers are permitted. For more information, see Section 23.3, “Using Triggers”.Logging. These logging enhancements were added:
Previously, on Unix and Unix-like systems, MySQL support for sending the server error log to
syslog
was implemented by having mysqld_safe capture server error output and pass it tosyslog
. The server now includes nativesyslog
support, which has been extended to include Windows. For more information about sending server error output tosyslog
, see Section 5.4.2, “The Error Log”.The mysql client now has a
--syslog
option that causes interactive statements to be sent to the systemsyslog
facility. Logging is suppressed for statements that match the default “ignore” pattern list ("*IDENTIFIED*:*PASSWORD*"
), as well as statements that match any patterns specified using the--histignore
option. See Section 4.5.1.3, “mysql Client Logging”.
Generated Columns. MySQL now supports the specification of generated columns in
CREATE TABLE
andALTER TABLE
statements. Values of a generated column are computed from an expression specified at column creation time. Generated columns can be virtual (computed “on the fly” when rows are read) or stored (computed when rows are inserted or updated). For more information, see Section 13.1.18.7, “CREATE TABLE and Generated Columns”.mysql client. Previously, Control+C in mysql interrupted the current statement if there was one, or exited mysql if not. Now Control+C interrupts the current statement if there was one, or cancels any partial input line otherwise, but does not exit.
Database name rewriting with mysqlbinlog. Renaming of databases by mysqlbinlog when reading from binary logs written using the row-based format is now supported using the
--rewrite-db
option added in MySQL 5.7.1.This option uses the format
--rewrite-db='
. You can implement multiple rewrite rules, by specifying the option multiple times.dboldname
->dbnewname
'HANDLER with partitioned tables. The
HANDLER
statement may now be used with user-partitioned tables. Such tables may use any of the available partitioning types (see Section 22.2, “Partitioning Types”).Index condition pushdown support for partitioned tables. Queries on partitioned tables using the
InnoDB
orMyISAM
storage engine may employ the index condition pushdown optimization that was introduced in MySQL 5.6. See Section 8.2.1.5, “Index Condition Pushdown Optimization”, for more information.WITHOUT VALIDATION support for ALTER TABLE ... EXCHANGE PARTITION. As of MySQL 5.7.5,
ALTER TABLE ... EXCHANGE PARTITION
syntax includes an optional{WITH|WITHOUT} VALIDATION
clause. WhenWITHOUT VALIDATION
is specified,ALTER TABLE ... EXCHANGE PARTITION
does not perform row-by-row validation when exchanging a populated table with the partition, permitting database administrators to assume responsibility for ensuring that rows are within the boundaries of the partition definition.WITH VALIDATION
is the default behavior and need not be specified explicitly. For more information, see Section 22.3.3, “Exchanging Partitions and Subpartitions with Tables”.Source dump thread improvements. The source dump thread was refactored to reduce lock contention and improve source throughput. Previous to MySQL 5.7.2, the dump thread took a lock on the binary log whenever reading an event; in MySQL 5.7.2 and later, this lock is held only while reading the position at the end of the last successfully written event. This means both that multiple dump threads are now able to read concurrently from the binary log file, and that dump threads are now able to read while clients are writing to the binary log.
Character set support. MySQL 5.7.4 includes a
gb18030
character set that supports the China National Standard GB18030 character set. For more information about MySQL character set support, see Chapter 10, Character Sets, Collations, Unicode.Changing the replication source without STOP SLAVE. In MySQL 5.7.4 and later, the strict requirement to execute
STOP SLAVE
prior to issuing anyCHANGE MASTER TO
statement is removed. Instead of depending on whether the replica is stopped, the behavior ofCHANGE MASTER TO
now depends on the states of the replica SQL thread and replica I/O threads; which of these threads is stopped or running now determines the options that can or cannot be used with aCHANGE MASTER TO
statement at a given point in time. The rules for making this determination are listed here:If the SQL thread is stopped, you can execute
CHANGE MASTER TO
using any combination ofRELAY_LOG_FILE
,RELAY_LOG_POS
, andMASTER_DELAY
options, even if the replica I/O thread is running. No other options may be used with this statement when the I/O thread is running.If the I/O thread is stopped, you can execute
CHANGE MASTER TO
using any of the options for this statement (in any allowed combination) exceptRELAY_LOG_FILE
,RELAY_LOG_POS
, orMASTER_DELAY
, even when the SQL thread is running. These three options may not be used when the I/O thread is running.Both the SQL thread and the I/O thread must be stopped before issuing
CHANGE MASTER TO ... MASTER_AUTO_POSITION = 1
.
You can check the current state of the replica SQL and I/O threads using
SHOW SLAVE STATUS
.If you are using statement-based replication and temporary tables, it is possible for a
CHANGE MASTER TO
statement following aSTOP SLAVE
statement to leave behind temporary tables on the replica. As part of this set of improvements, a warning is now issued wheneverCHANGE MASTER TO
is issued followingSTOP SLAVE
when statement-based replication is in use andSlave_open_temp_tables
remains greater than 0.For more information, see Section 13.4.2.1, “CHANGE MASTER TO Statement”, and Section 16.3.7, “Switching Sources During Failover”.
Test suite. The MySQL test suite now uses
InnoDB
as the default storage engine.Multi-source replication is now possible. MySQL Multi-Source Replication adds the ability to replicate from multiple sources to a replica. MySQL Multi-Source Replication topologies can be used to back up multiple servers to a single server, to merge table shards, and consolidate data from multiple servers to a single server. See Section 16.1.5, “MySQL Multi-Source Replication”.
As part of MySQL Multi-Source Replication, replication channels have been added. Replication channels enable a replica to open multiple connections to replicate from, with each channel being a connection to a source. See Section 16.2.2, “Replication Channels”.
Group Replication Performance Schema tables. MySQL 5.7 adds a number of new tables to the Performance Schema to provide information about replication groups and channels. These include the following tables:
All of these tables were added in MySQL 5.7.2, except for
replication_group_members
andreplication_group_member_stats
, which were added in MySQL 5.7.6. For more information, see Section 25.12.11, “Performance Schema Replication Tables”.Group Replication SQL. The following statements were added in MySQL 5.7.6 for controlling Group Replication:
For more information, see Section 13.4.3, “SQL Statements for Controlling Group Replication”.
The following features are deprecated in MySQL 5.7 and may be removed in a future series. Where alternatives are shown, applications should be updated to use them.
For applications that use features deprecated in MySQL 5.7 that have been removed in a higher MySQL series, statements may fail when replicated from a MySQL 5.7 source to a higher-series replica, or may have different effects on source and replica. To avoid such problems, applications that use features deprecated in 5.7 should be revised to avoid them and use alternatives when possible.
The
ERROR_FOR_DIVISION_BY_ZERO
,NO_ZERO_DATE
, andNO_ZERO_IN_DATE
SQL modes are now deprecated but enabled by default. The long term plan is to have them included in strict SQL mode and to remove them as explicit modes in a future MySQL release.The deprecated
ERROR_FOR_DIVISION_BY_ZERO
,NO_ZERO_DATE
, andNO_ZERO_IN_DATE
SQL modes are still recognized so that statements that name them do not produce an error, but are expected to be removed in a future version of MySQL. To make advance preparation for versions of MySQL in which these mode names do not exist, applications should be modified not to refer to them. See SQL Mode Changes in MySQL 5.7.These SQL modes are now deprecated; expect them to be removed in a future version of MySQL:
DB2
,MAXDB
,MSSQL
,MYSQL323
,MYSQL40
,ORACLE
,POSTGRESQL
,NO_FIELD_OPTIONS
,NO_KEY_OPTIONS
,NO_TABLE_OPTIONS
. These deprecations have two implications:Assigning a deprecated mode to the
sql_mode
system variable produces a warning.With the
MAXDB
SQL mode enabled, usingCREATE TABLE
orALTER TABLE
to add aTIMESTAMP
column to a table produces a warning.
Changes to account-management statements make the following features obsolete. They are now deprecated:
Using
GRANT
to create users. Instead, useCREATE USER
. Following this practice makes theNO_AUTO_CREATE_USER
SQL mode immaterial forGRANT
statements, so it too is deprecated.Using
GRANT
to modify account properties other than privilege assignments. This includes authentication, SSL, and resource-limit properties. Instead, establish such properties at account-creation time withCREATE USER
or modify them afterward withALTER USER
.IDENTIFIED BY PASSWORD '
syntax forauth_string
'CREATE USER
andGRANT
. Instead, useIDENTIFIED WITH
forauth_plugin
AS 'auth_string
'CREATE USER
andALTER USER
, where the'
value is in a format compatible with the named plugin.auth_string
'The
PASSWORD()
function is deprecated and should be avoided in any context. Thus,SET PASSWORD ... = PASSWORD('
syntax is also deprecated.auth_string
')SET PASSWORD ... = '
syntax is not deprecated; nevertheless,auth_string
'ALTER USER
is now the preferred statement for assigning passwords.The
old_passwords
system variable. Account authentication plugins can no longer be left unspecified in themysql.user
system table, so any statement that assigns a password from a cleartext string can unambiguously determine the hashing method to use on the string before storing it in themysql.user
table. This rendersold_passwords
superflous.
The query cache is deprecated. Deprecation includes these items:
The
FLUSH QUERY CACHE
andRESET QUERY CACHE
statements.The
SQL_CACHE
andSQL_NO_CACHE
SELECT
modifiers.These system variables:
have_query_cache
,ndb_cache_check_time
,query_cache_limit
,query_cache_min_res_unit
,query_cache_size
,query_cache_type
,query_cache_wlock_invalidate
.These status variables:
Qcache_free_blocks
,Qcache_free_memory
,Qcache_hits
,Qcache_inserts
,Qcache_lowmem_prunes
,Qcache_not_cached
,Qcache_queries_in_cache
,Qcache_total_blocks
.
Previously, the
--transaction-isolation
and--transaction-read-only
server startup options corresponded to thetx_isolation
andtx_read_only
system variables. For better name correspondence between startup option and system variable names,transaction_isolation
andtransaction_read_only
have been created as aliases fortx_isolation
andtx_read_only
. Thetx_isolation
andtx_read_only
variables are now deprecated;expect them to be removed in MySQL 8.0. Applications should be adjusted to usetransaction_isolation
andtransaction_read_only
instead.The
--skip-innodb
option and its synonyms (--innodb=OFF
,--disable-innodb
, and so forth) are deprecated. These options have no effect as of MySQL 5.7. becauseInnoDB
cannot be disabled.The client-side
--ssl
and--ssl-verify-server-cert
options are deprecated. Use--ssl-mode=REQUIRED
instead of--ssl=1
or--enable-ssl
. Use--ssl-mode=DISABLED
instead of--ssl=0
,--skip-ssl
, or--disable-ssl
. Use--ssl-mode=VERIFY_IDENTITY
instead of--ssl-verify-server-cert
options. (The server-side--ssl
option is not deprecated.)For the C API,
MYSQL_OPT_SSL_ENFORCE
andMYSQL_OPT_SSL_VERIFY_SERVER_CERT
options formysql_options()
correspond to the client-side--ssl
and--ssl-verify-server-cert
options and are deprecated. UseMYSQL_OPT_SSL_MODE
with an option value ofSSL_MODE_REQUIRED
orSSL_MODE_VERIFY_IDENTITY
instead.The
log_warnings
system variable and--log-warnings
server option are deprecated. Use thelog_error_verbosity
system variable instead.The
--temp-pool
server option is deprecated.The
binlog_max_flush_queue_time
system variable does nothing in MySQL 5.7, and is deprecated as of MySQL 5.7.9.The
innodb_support_xa
system variable, which enablesInnoDB
support for two-phase commit in XA transactions, is deprecated as of MySQL 5.7.10.InnoDB
support for two-phase commit in XA transactions is always enabled as of MySQL 5.7.10.The
metadata_locks_cache_size
andmetadata_locks_hash_instances
system variables are deprecated. These do nothing as of MySQL 5.7.4.The
sync_frm
system variable is deprecated.The global
character_set_database
andcollation_database
system variables are deprecated; expect them to be removed in a future version of MySQL.Assigning a value to the session
character_set_database
andcollation_database
system variables is deprecated and assignments produce a warning. The session variables are expected to become read only in a future version of MySQL, and assignments to them to produce an error, while remaining possible to read the session variables to determine the database character set and collation for the default database.The global scope for the
sql_log_bin
system variable has been deprecated, and this variable can now be set with session scope only. The statementSET GLOBAL SQL_LOG_BIN
now produces an error. It remains possible to read the global value ofsql_log_bin
, but doing so produces a warning. You should act now to remove from your applications any dependencies on reading this value; the global scopesql_log_bin
is removed in MySQL 8.0.With the introduction of the data dictionary in MySQL 8.0, the
--ignore-db-dir
option andignore_db_dirs
system variable became superfluous and were removed in that version. Consequently, they are deprecated in MySQL 5.7.GROUP BY
implicitly sorts by default (that is, in the absence ofASC
orDESC
designators), but relying on implicitGROUP BY
sorting in MySQL 5.7 is deprecated. To achieve a specific sort order of grouped results, it is preferable to use To produce a given sort order, use explicitASC
orDESC
designators forGROUP BY
columns or provide anORDER BY
clause.GROUP BY
sorting is a MySQL extension that may change in a future release; for example, to make it possible for the optimizer to order groupings in whatever manner it deems most efficient and to avoid the sorting overhead.The
EXTENDED
andPARTITIONS
keywords for theEXPLAIN
statement are deprecated. These keywords are still recognized but are now unnecessary because their effect is always enabled.The
ENCRYPT()
,ENCODE()
,DECODE()
,DES_ENCRYPT()
, andDES_DECRYPT()
encryption functions are deprecated. ForENCRYPT()
, consider usingSHA2()
instead for one-way hashing. For the others, consider usingAES_ENCRYPT()
andAES_DECRYPT()
instead. The--des-key-file
option, thehave_crypt
system variable, theDES_KEY_FILE
option for theFLUSH
statement, and theHAVE_CRYPT
CMake option also are deprecated.The
MBREqual()
spatial function is deprecated. UseMBREquals()
instead.The functions described in Section 12.16.4, “Functions That Create Geometry Values from WKB Values” previously accepted either WKB strings or geometry arguments. Use of geometry arguments is deprecated. See that section for guidelines for migrating queries away from using geometry arguments.
The
INFORMATION_SCHEMA
PROFILING
table is deprecated. Use the Performance Schema instead; see Chapter 25, MySQL Performance Schema.The
INFORMATION_SCHEMA
INNODB_LOCKS
andINNODB_LOCK_WAITS
tables are deprecated, to be removed in MySQL 8.0, which provides replacement Performance Schema tables.The Performance Schema
setup_timers
table is deprecated and is removed in MySQL 8.0, as is theTICK
row in theperformance_timers
table.The
sys
schemasys.version
view is deprecated; expect it be removed in a future version of MySQL. Affected applications should be adjusted to use an alternative instead. For example, use theVERSION()
function to retrieve the MySQL server version.Treatment of
\N
as a synonym forNULL
in SQL statements is deprecated and is removed in MySQL 8.0; useNULL
instead.This change does not affect text file import or export operations performed with
LOAD DATA
orSELECT ... INTO OUTFILE
, for whichNULL
continues to be represented by\N
. See Section 13.2.6, “LOAD DATA Statement”.PROCEDURE ANALYSE()
syntax is deprecated.Comment stripping by the mysql client and the options to control it (
--skip-comments
,--comments
) are deprecated.mysqld_safe support for
syslog
output is deprecated. Use the native serversyslog
support used instead. See Section 5.4.2, “The Error Log”.Conversion of pre-MySQL 5.1 database names containing special characters to 5.1 format with the addition of a
#mysql50#
prefix is deprecated. Because of this, the--fix-db-names
and--fix-table-names
options for mysqlcheck and theUPGRADE DATA DIRECTORY NAME
clause for theALTER DATABASE
statement are also deprecated.Upgrades are supported only from one release series to another (for example, 5.0 to 5.1, or 5.1 to 5.5), so there should be little remaining need for conversion of older 5.0 database names to current versions of MySQL. As a workaround, upgrade a MySQL 5.0 installation to MySQL 5.1 before upgrading to a more recent release.
mysql_install_db functionality has been integrated into the MySQL server, mysqld. To use this capability to initialize a MySQL installation, if you previously invoked mysql_install_db manually, invoke mysqld with the
--initialize
or--initialize-insecure
option, depending on whether you want the server to generate a random password for the initial'root'@'localhost'
account.mysql_install_db is now deprecated, as is the special
--bootstrap
option that mysql_install_db passes to mysqld.The mysql_plugin utility is deprecated. Alternatives include loading plugins at server startup using the
--plugin-load
or--plugin-load-add
option, or at runtime using theINSTALL PLUGIN
statement.The resolveip utility is deprecated. nslookup, host, or dig can be used instead.
The resolve_stack_dump utility is deprecated. Stack traces from official MySQL builds are always symbolized, so there is no need to use resolve_stack_dump.
The
mysql_kill()
,mysql_list_fields()
,mysql_list_processes()
, andmysql_refresh()
C API functions are deprecated. The same is true of the correspondingCOM_PROCESS_KILL
,COM_FIELD_LIST
,COM_PROCESS_INFO
, andCOM_REFRESH
client/server protocol commands. Instead, usemysql_query()
to execute aKILL
,SHOW COLUMNS
,SHOW PROCESSLIST
, orFLUSH
statement, respectively.The
mysql_shutdown()
C API function is deprecated. Instead, usemysql_query()
to execute aSHUTDOWN
statement.The
libmysqld
embedded server library is deprecated as of MySQL 5.7.19. These are also deprecated:The mysql_config
--libmysqld-libs
,--embedded-libs
, and--embedded
optionsThe CMake
WITH_EMBEDDED_SERVER
,WITH_EMBEDDED_SHARED_LIBRARY
, andINSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR
optionsThe (undocumented) mysql
--server-arg
optionThe mysqltest
--embedded-server
,--server-arg
, and--server-file
optionsThe mysqltest_embedded and mysql_client_test_embedded test programs
Because
libmysqld
uses an API comparable to that oflibmysqlclient
, the migration path away fromlibmysqld
is straightforward:Bring up a standalone MySQL server (mysqld).
Modify application code to remove API calls that are specific to
libmysqld
.Modify application code to connect to the standalone MySQL server.
Modify build scripts to use
libmysqlclient
rather thanlibmysqld
. For example, if you use mysql_config, invoke it with the--libs
option rather than--libmysqld-libs
.
The replace utility is deprecated.
Support for DTrace is deprecated.
The
JSON_MERGE()
function is deprecated as of MySQL 5.7.22. UseJSON_MERGE_PRESERVE()
instead.Support for placing table partitions in shared
InnoDB
tablespaces is deprecated as of MySQL 5.7.24. Shared tablespaces include theInnoDB
system tablespace and general tablespaces. For information about identifying partitions in shared tablespaces and moving them to file-per-table tablespaces, see Preparing Your Installation for Upgrade.Support for
TABLESPACE = innodb_file_per_table
andTABLESPACE = innodb_temporary
clauses withCREATE TEMPORARY TABLE
is deprecated as of MySQL 5.7.24.The
--ndb
perror option is deprecated. Use the ndb_perror utility instead.The
myisam_repair_threads
system variablemyisam_repair_threads
are deprecated as of MySQL 5.7.38; expect support for both to be removed in a future release of MySQL.From MySQL 5.7.38, values other than 1 (the default) for
myisam_repair_threads
produce a warning.
The following items are obsolete and have been removed in MySQL 5.7. Where alternatives are shown, applications should be updated to use them.
For MySQL 5.6 applications that use features removed in MySQL 5.7, statements may fail when replicated from a MySQL 5.6 source to a MySQL 5.7 replica, or may have different effects on source and replica. To avoid such problems, applications that use features removed in MySQL 5.7 should be revised to avoid them and use alternatives when possible.
Support for passwords that use the older pre-4.1 password hashing format is removed, which involves the following changes. Applications that use any feature no longer supported must be modified.
The
mysql_old_password
authentication plugin is removed. Accounts that use this plugin are disabled at startup and the server writes an “unknown plugin” message to the error log. For instructions on upgrading accounts that use this plugin, see Section 6.4.1.3, “Migrating Away from Pre-4.1 Password Hashing and the mysql_old_password Plugin”.The
--secure-auth
option to the server and client programs is the default, but is now a no-op. It is deprecated; expect it to be removed in a future MySQL release.The
--skip-secure-auth
option to the server and client programs is no longer supported and using it produces an error.The
secure_auth
system variable permits only a value of 1; a value of 0 is no longer permitted.For the
old_passwords
system variable, a value of 1 (produce pre-4.1 hashes) is no longer permitted.The
OLD_PASSWORD()
function is removed.
In MySQL 5.6.6, the 2-digit
YEAR(2)
data type was deprecated. Support forYEAR(2)
is now removed. Once you upgrade to MySQL 5.7.5 or higher, any remaining 2-digitYEAR(2)
columns must be converted to 4-digitYEAR
columns to become usable again. For conversion strategies, see Section 11.2.5, “2-Digit YEAR(2) Limitations and Migrating to 4-Digit YEAR”. For example, run mysql_upgrade after upgrading.The
innodb_mirrored_log_groups
system variable. The only supported value was 1, so it had no purpose.The
storage_engine
system variable. Usedefault_storage_engine
instead.The
thread_concurrency
system variable.The
timed_mutexes
system variable, which had no effect.The
IGNORE
clause forALTER TABLE
.INSERT DELAYED
is no longer supported. The server recognizes but ignores theDELAYED
keyword, handles the insert as a nondelayed insert, and generates anER_WARN_LEGACY_SYNTAX_CONVERTED
warning. (“INSERT DELAYED is no longer supported. The statement was converted to INSERT.”) Similarly,REPLACE DELAYED
is handled as a nondelayed replace. You should expect theDELAYED
keyword to be removed in a future release.In addition, several
DELAYED
-related options or features were removed:The
--delayed-insert
option for mysqldump.The
COUNT_WRITE_DELAYED
,SUM_TIMER_WRITE_DELAYED
,MIN_TIMER_WRITE_DELAYED
,AVG_TIMER_WRITE_DELAYED
, andMAX_TIMER_WRITE_DELAYED
columns of the Performance Schematable_lock_waits_summary_by_table
table.mysqlbinlog no longer writes comments mentioning
INSERT DELAYED
.
Database symlinking on Windows using
.sym
files has been removed because it is redundant with native symlink support available using mklink. Any.sym
file symbolic links are now ignored and should be replaced with symlinks created using mklink. See Section 8.12.3.3, “Using Symbolic Links for Databases on Windows”.The unused
--basedir
,--datadir
, and--tmpdir
options for mysql_upgrade were removed.Previously, program options could be specified in full or as any unambiguous prefix. For example, the
--compress
option could be given to mysqldump as--compr
, but not as--comp
because the latter is ambiguous. Option prefixes are no longer supported; only full options are accepted. This is because prefixes can cause problems when new options are implemented for programs and a prefix that is currently unambiguous might become ambiguous in the future. Some implications of this change:The
--key-buffer
option must now be specified as--key-buffer-size
.The
--skip-grant
option must now be specified as--skip-grant-tables
.
SHOW ENGINE INNODB MUTEX
output is removed. Comparable information can be generated by creating views on Performance Schema tables.The
InnoDB
Tablespace Monitor andInnoDB
Table Monitor are removed. For the Table Monitor, equivalent information can be obtained fromInnoDB
INFORMATION_SCHEMA
tables.The specially named tables used to enable and disable the standard
InnoDB
Monitor andInnoDB
Lock Monitor (innodb_monitor
andinnodb_lock_monitor
) are removed and replaced by two dynamic system variables:innodb_status_output
andinnodb_status_output_locks
. For additional information, see Section 14.18, “InnoDB Monitors”.The
innodb_use_sys_malloc
andinnodb_additional_mem_pool_size
system variables, deprecated in MySQL 5.6.3, were removed.The msql2mysql, mysql_convert_table_format, mysql_find_rows, mysql_fix_extensions, mysql_setpermission, mysql_waitpid, mysql_zap, mysqlaccess, and mysqlbug utilities.
The mysqlhotcopy utility. Alternatives include mysqldump and MySQL Enterprise Backup.
The binary-configure.sh script.
The
INNODB_PAGE_ATOMIC_REF_COUNT
CMake option is removed.The
innodb_create_intrinsic
option is removed.The
innodb_optimize_point_storage
option and related internal data types (DATA_POINT
andDATA_VAR_POINT
) are removed.The
innodb_log_checksum_algorithm
option is removed.The
myisam_repair_threads
system variable as of MySQL 5.7.39.