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13.1.4 Floating-Point Types (Approximate Value) - FLOAT, DOUBLE

https://dev.mysql.com/doc/refman/8.0/en/floating-point-types.html

MySQL permits a nonstandard syntax: FLOAT(M,D) or REAL(M,D) or DOUBLE PRECISION(M,D). The FLOAT and DOUBLE types represent approximate numeric data values. MySQL uses four bytes for single-precision values and eight bytes for double-precision ...

14.5 Flow Control Functions

https://dev.mysql.com/doc/refman/8.0/en/flow-control-functions.html

mysql> SELECT IFNULL(1,0); -> 1 mysql> SELECT IFNULL(NULL,10); -> 10 mysql> SELECT IFNULL(1/0,10); -> 10 mysql> SELECT IFNULL(1/0,'yes'); -> 'yes' The default return type of IFNULL(expr1,expr2) is the more “general” of the two expressions, in ...

20.7.2.2 Group Replication Throttling

https://dev.mysql.com/doc/refman/8.0/en/group-replication-throttling.html

The lowest capacity of all the members in the group determines the real capacity of the group, while the number of local transactions determines how many members are writing to it, and, consequently, how many members should that available capacity ... Based on the metrics gathered across all servers in the group, a throttling mechanism kicks in and decides whether to limit the rate a member is able to execute/commit new ...

28.4.20 The INFORMATION_SCHEMA INNODB_INDEXES Table

https://dev.mysql.com/doc/refman/8.0/en/information-schema-innodb-indexes-table.html

For GEN_CLUST_INDEX indexes, this value is 0 because the index is created using an artificial value rather than a real table column. For related usage information and examples, see Section 17.15.3, “InnoDB INFORMATION_SCHEMA Schema Object ...

25.4.3.9 MySQL Server Options and Variables for NDB Cluster

https://dev.mysql.com/doc/refman/8.0/en/mysql-cluster-options-variables.html

The real (internal) name of the table can be seen in the output of SHOW CREATE TABLE. Ndb_conflict_trans_row_reject_count Used in NDB Cluster Replication conflict resolution, this status variable shows the total number of rows realigned due to being ... This section provides information about MySQL server options, server and status variables that are specific to NDB ...

17.9.1.7 SQL Compression Syntax Warnings and Errors

https://dev.mysql.com/doc/refman/8.0/en/innodb-compression-syntax-warnings.html

The real compressed page size of the table cannot be displayed by MySQL. This section describes syntax warnings and errors that you may encounter when using the table compression feature with file-per-table tablespaces and general tablespaces. SQL ...

17.7.1 InnoDB Locking

https://dev.mysql.com/doc/refman/8.0/en/innodb-locking.html

The supremum is not a real index record, so, in effect, this next-key lock locks only the gap following the largest index value. Shared and Exclusive Locks Intention Locks Record Locks Gap Locks Next-Key Locks Insert Intention Locks AUTO-INC Locks ...

17.20.8 InnoDB memcached Plugin Internals

https://dev.mysql.com/doc/refman/8.0/en/innodb-memcached-internals.html

If the number sent by a client is larger, the server considers it to be a real Unix time value rather than an offset from the current time. InnoDB API for the InnoDB memcached Plugin The InnoDB memcached engine accesses InnoDB through InnoDB APIs, ...

17.20.6.1 Adapting an Existing MySQL Schema for the InnoDB memcached Plugin

https://dev.mysql.com/doc/refman/8.0/en/innodb-memcached-porting-mysql.html

A more descriptive name value might be used in a real-world application. Consider these aspects of memcached applications when adapting an existing MySQL schema or application to use the daemon_memcached plugin: memcached keys cannot contain spaces ...

17.14 InnoDB Startup Options and System Variables

https://dev.mysql.com/doc/refman/8.0/en/innodb-parameters.html

Because the adaptive hash index may not be useful for all workloads, conduct benchmarks with it both enabled and disabled, using realistic workloads. Setting a limit on this value reduces the size of the index, thus speeding up queries, by omitting ... InnoDB Startup Options InnoDB System Variables System variables that are true or false can be enabled at server startup by naming them, or disabled by using a --skip- ...

Displaying 51 to 60 of 69 total results