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COUNT READWRITE_SPLITTING RULE

描述

COUNT READWRITE_SPLITTING RULE 语法用于查询指定逻辑库中的读写分离规则数量。

语法

CountReadwriteSplittingRule::=
  'COUNT' 'READWRITE_SPLITTING' 'RULE' ('FROM' databaseName)?

databaseName ::=
  identifier

补充说明

  • 未指定 databaseName 时,默认是当前使用的 DATABASE。 如果也未使用 DATABASE 则会提示 No database selected

返回值说明

说明
rule_name 规则类型
database 规则所属逻辑库
count 规则数量

示例

  • 查询指定逻辑库中的读写分离规则数量
COUNT READWRITE_SPLITTING RULE FROM readwrite_splitting_db;
mysql> COUNT READWRITE_SPLITTING RULE FROM readwrite_splitting_db;
+---------------------+---------------------------+-------+
| rule_name           | database                  | count |
+---------------------+---------------------------+-------+
| readwrite_splitting | readwrite_splitting_db    | 1     |
+---------------------+---------------------------+-------+
1 row in set (0.02 sec)
  • 查询当前逻辑库中的读写分离规则数量
COUNT READWRITE_SPLITTING RULE;
mysql> COUNT READWRITE_SPLITTING RULE;
+---------------------+---------------------------+-------+
| rule_name           | database                  | count |
+---------------------+---------------------------+-------+
| readwrite_splitting | readwrite_splitting_db    | 1     |
+---------------------+---------------------------+-------+
1 row in set (0.00 sec)

保留字

COUNTREADWRITE_SPLITTINGRULEFROM

相关链接