| Query goal: | Triggers can be used to maintain data integrity in a database by causing rejection of data that does not conform to certain rules. Therefore, the number of triggers in a database gives an indication about the state of enforcing constraints at the database level. |
| Notes about the query: | The query counts table triggers (associated with a table and reacting to a data modification in it) and event triggers. It counts these over all the different schemas that contain user-defined schema objects. It discards triggers that the system creates automatically to enforce referential integrity. If one trigger is associated with multiple events (for instance, INSERT and UPDATE), then it counts it as one trigger. The query only returns data about schemas that have at least one table trigger. |
| Query type: | Sofware measure (Numeric values (software measures) about the database) |
| Query license: | MIT License |
| Data source: | INFORMATION_SCHEMA+system catalog |
| SQL query: | Click on query to copy it
WITH triggers AS ( SELECT trigger_schema, 'TABLE TRIGGER' AS trigger_type, event_object_table, trigger_name FROM information_schema.triggers AS Tr INNER JOIN information_schema.schemata S ON Tr.trigger_schema=S.schema_name WHERE (Tr.trigger_schema = 'public' OR S.schema_owner<>'postgres') UNION ALL SELECT '' AS trigger_schema, 'EVENT TRIGGER' AS trigger_type, '' AS event_object_table, evtname AS trigger_name FROM pg_catalog.pg_event_trigger) SELECT trigger_schema, trigger_type, Count(DISTINCT event_object_table ||'.'|| trigger_name) AS number_of_triggers FROM triggers GROUP BY CUBE(trigger_schema, trigger_type) ORDER BY trigger_schema, trigger_type; |
| Collection name | Collection description |
|---|---|
| Find problems by overview | Queries that results point to different aspects of database that might have problems. A human reviewer has to decide based on the results as to whether there are problems or not . |
| Find quick numeric overview of the database | Queries that return numeric values showing mostly the number of different types of database objects in the database |
| Category name | Category description |
|---|---|
| Triggers and rules | Queries of this category provide information about triggers and rules in a database. |