COUNT BROADCAST RULE

Description

The COUNT BROADCAST RULE syntax is used to query the number of broadcast table rules for specified database.

Syntax

Grammar Railroad diagram

  1. CountBroadcastRule::=
  2.   'COUNT' 'BROADCAST' 'RULE' ('FROM' databaseName)?
  4. databaseName ::=
  5.   identifier

Supplement

  • When databaseName is not specified, the default is the currently used DATABASE. If DATABASE is not used, No database selected will be prompted.

Return value description

ColumnDescription
rule_namerule type
databasethe database to which the rule belongs
countthe number of the rule

Example

  • Query the number of broadcast table rules for specified database.
  1. COUNT BROADCAST RULE FROM sharding_db;
  1. mysql> COUNT BROADCAST RULE FROM sharding_db;
  2. +--------------------------+----------------+-------+
  3. | rule_name                | database       | count |
  4. +--------------------------+----------------+-------+
  5. | broadcast_table          | sharding_db    | 0     |
  6. +--------------------------+----------------+-------+
  7. 1 rows in set (0.00 sec)
  • Query the number of broadcast table rules for current database.
  1. COUNT BROADCAST RULE;
  1. mysql> COUNT BROADCAST RULE;
  2. +--------------------------+----------------+-------+
  3. | rule_name                | database       | count |
  4. +--------------------------+----------------+-------+
  5. | broadcast_table          | sharding_db    | 0     |
  6. +--------------------------+----------------+-------+
  7. 1 rows in set (0.00 sec)

Reserved word

COUNT, BROADCAST, RULE, FROM