| Query goal: | Find the number of textual base table columns, the number of optional textual base table columns (permit NULLs), and the number of mandatory textual base table columns (do not permit NULLs). |
| Query type: | Sofware measure (Numeric values (software measures) about the database) |
| Query license: | MIT License |
| Data source: | INFORMATION_SCHEMA only |
| SQL query: | Click on query to copy it
SELECT Count(*) FILTER (WHERE is_nullable='NO') AS number_of_mandatory_textual_columns, Count(*) FILTER (WHERE is_nullable='YES') AS number_of_optional_textual_columns, Count(*) AS number_of_textual_columns FROM information_schema.columns A INNER JOIN information_schema.schemata S ON A.table_schema=S.schema_name WHERE A.data_type IN ('character varying','text','character') AND (A.table_schema = 'public' OR S.schema_owner<>'postgres') AND (table_schema, table_name) IN (SELECT table_schema, table_name FROM information_schema.tables WHERE table_type='BASE TABLE'); |
| Collection name | Collection description |
|---|---|
| Find problems about integrity constraints | A selection of queries that return information about the state of integrity constraints in the datadabase. Contains all the types of queries - problem detection, software measure, and general overview |
| 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 |
|---|---|
| Missing data | Queries of this category provide information about missing data (NULLs) in a database. |