Query goal: | Find table columns with CHAR or VARCHAR type that have a default value that length is longer from the character maximum length of the column. Choose a suitable data type, field size, and default value. If the value is longer, then it is impossible to register it in a field, i.e., it makes registration of data impossible (except if the excessive characters are spaces). |
Query type: | Problem detection (Each row in the result could represent a flaw in the design) |
Query reliability: | High (Few or no false-positive results) |
Query license: | MIT License |
Fixing suggestion: | Increase the field size or shorthen the default value. |
Data source: | INFORMATION_SCHEMA only |
SQL query: | Click on query to copy it
WITH defaults AS (SELECT c.table_schema, t.table_type, c.table_name, c.column_name, CASE WHEN column_default IS NOT NULL THEN 'COLUMN' ELSE 'DOMAIN' END AS object_type, c.data_type, c.character_maximum_length, coalesce(c.column_default, domain_default) AS def_value FROM information_schema.columns AS c LEFT JOIN information_schema.domains d ON c.domain_schema=d.domain_schema AND c.domain_name=d.domain_name INNER JOIN INFORMATION_SCHEMA.tables AS t USING (table_schema, table_name) WHERE c.table_schema NOT IN (SELECT schema_name FROM INFORMATION_SCHEMA.schemata WHERE schema_name<>'public' AND schema_owner='postgres' AND schema_name IS NOT NULL) AND c.data_type IN ('character', 'character varying' ) AND (coalesce(c.column_default, domain_default) LIKE '%::bpchar' OR coalesce(c.column_default, domain_default) LIKE '%::character varying') AND (column_default IS NOT NULL OR domain_default IS NOT NULL) ORDER BY c.table_schema, c.table_name, c.ordinal_position) SELECT table_schema, table_type, table_name, column_name, character_maximum_length, data_type, def_value, object_type FROM defaults WHERE char_length(trim(substring(def_value,'[''][^'']*['']'),'''')) >character_maximum_length ORDER BY table_type, table_schema, table_name; |
Collection name | Collection description |
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Find problems automatically | Queries, that results point to problems in the database. Each query in the collection produces an initial assessment. However, a human reviewer has the final say as to whether there is a problem or not . |
Category name | Category description |
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Data types | Queries of this category provide information about the data types and their usage. |
Default value | Queries of this catergory provide information about the use of default values. |
Fatal problems | Queries of this category provide information about problems that render a part of a database unusable. |
Validity and completeness | Queries of this category provide information about whether database design represents the world (domain) correctly (validity) and whether database design captures all the information about the world (domain) that is correct and relevant (completeness). |