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

https://dev.mysql.com/doc/refman/9.7/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/9.7/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/9.7/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/9.7/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 ...

25.2 NDB Cluster Overview

https://dev.mysql.com/doc/refman/9.7/en/mysql-cluster-overview.html

NDB Cluster nodes can employ different transport mechanisms for inter-node communications; TCP/IP over standard 100 Mbps or faster Ethernet hardware is used in most real-world deployments. NDB Cluster is a technology that enables clustering of ...

17.9.1.7 SQL Compression Syntax Warnings and Errors

https://dev.mysql.com/doc/refman/9.7/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/9.7/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 ...

17.14 InnoDB Startup Options and System Variables

https://dev.mysql.com/doc/refman/9.7/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- ...

10.11.1 Internal Locking Methods

https://dev.mysql.com/doc/refman/9.7/en/internal-locking.html

This section discusses internal locking; that is, locking performed within the MySQL server itself to manage contention for table contents by multiple sessions. This type of locking is internal because it is performed entirely by the server and ...

11.3 Keywords and Reserved Words

https://dev.mysql.com/doc/refman/9.7/en/keywords.html

Certain keywords, such as SELECT, DELETE, or BIGINT, are reserved and require special treatment for use as identifiers such as table and column names. This may also be true for the names of built-in functions. Some keywords which are otherwise ...

Displaying 51 to 60 of 68 total results