COUNT DB_DISCOVERY RULE

Description

The COUNT DB_DISCOVERY RULE syntax is used to query the number of database discovery rules for specified database.

Syntax

Grammar Railroad diagram

  1. CountDBDiscoveryRule::=
  2.   'COUNT' 'DB_DISCOVERY' '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 database discovery rules for specified database.
  1. COUNT DB_DISCOVERY RULE FROM discovery_db;
  1. mysql> COUNT DB_DISCOVERY RULE FROM discovery_db;
  2. +--------------+-----------------+-------+
  3. | rule_name    | database        | count |
  4. +--------------+-----------------+-------+
  5. | db_discovery | discovery_db    | 1     |
  6. +--------------+-----------------+-------+
  7. 1 row in set (0.00 sec)
  • Query the number of database discovery rules for current database.
  1. COUNT DB_DISCOVERY RULE;
  1. mysql> COUNT DB_DISCOVERY RULE;
  2. +--------------+-----------------+-------+
  3. | rule_name    | database        | count |
  4. +--------------+-----------------+-------+
  5. | db_discovery | discovery_db    | 1     |
  6. +--------------+-----------------+-------+
  7. 1 row in set (0.00 sec)

Reserved word

COUNT, DB_DISCOVERY, RULE, FROM