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
CountDBDiscoveryRule::=
'COUNT' 'DB_DISCOVERY' 'RULE' ('FROM' databaseName)?
databaseName ::=
identifier
Supplement
- When
databaseName
is not specified, the default is the currently usedDATABASE
. IfDATABASE
is not used,No database selected
will 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 database discovery rules for specified database.
COUNT DB_DISCOVERY RULE FROM test1;
mysql> COUNT DB_DISCOVERY RULE FROM test1;
+--------------+----------+-------+
| rule_name | database | count |
+--------------+----------+-------+
| db_discovery | test1 | 1 |
+--------------+----------+-------+
1 row in set (0.00 sec)
- Query the number of database discovery rules for current database.
COUNT DB_DISCOVERY RULE;
mysql> COUNT DB_DISCOVERY RULE;
+--------------+----------+-------+
| rule_name | database | count |
+--------------+----------+-------+
| db_discovery | test1 | 1 |
+--------------+----------+-------+
1 row in set (0.00 sec)
Reserved word
COUNT
, DB_DISCOVERY
, RULE
, FROM
Related links
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