COUNT BROADCAST RULE
Description
The COUNT BROADCAST RULE syntax is used to query the number of broadcast table rules for specified database.
Syntax
CountBroadcastRule::=
'COUNT' 'BROADCAST' 'RULE' ('FROM' databaseName)?
databaseName ::=
identifierSupplement
- When
databaseNameis not specified, the default is the currently usedDATABASE. IfDATABASEis not used,No database selectedwill be prompted.
Return value description
| Column | Description |
|---|---|
| rule_name | rule type |
| database | the database to which the rule belongs |
| count | the number of the rule |
Example
- Query the number of broadcast table rules for specified database.
COUNT BROADCAST RULE FROM sharding_db;mysql> COUNT BROADCAST RULE FROM sharding_db;
+--------------------------+----------------+-------+
| rule_name | database | count |
+--------------------------+----------------+-------+
| broadcast_table | sharding_db | 0 |
+--------------------------+----------------+-------+
1 row in set (0.00 sec)- Query the number of broadcast table rules for current database.
COUNT BROADCAST RULE;mysql> COUNT BROADCAST RULE;
+--------------------------+----------------+-------+
| rule_name | database | count |
+--------------------------+----------------+-------+
| broadcast_table | sharding_db | 0 |
+--------------------------+----------------+-------+
1 row in set (0.00 sec)Reserved word
COUNT, BROADCAST, RULE, FROM