36.32. key_column_usage

檢視表 key_column_usage 列出目前資料庫中受到某些唯一、主鍵或外部鍵限制的所有欄位。此檢視表中不包括 check constraints。僅顯示目前使用者可以透過成為擁有者或具有某些權限存取的那些欄位。

Table 36.30. key_column_usage Columns

NameData TypeDescription

constraint_catalog

sql_identifier

Name of the database that contains the constraint (always the current database)

constraint_schema

sql_identifier

Name of the schema that contains the constraint

constraint_name

sql_identifier

Name of the constraint

table_catalog

sql_identifier

Name of the database that contains the table that contains the column that is restricted by this constraint (always the current database)

table_schema

sql_identifier

Name of the schema that contains the table that contains the column that is restricted by this constraint

table_name

sql_identifier

Name of the table that contains the column that is restricted by this constraint

column_name

sql_identifier

Name of the column that is restricted by this constraint

ordinal_position

cardinal_number

Ordinal position of the column within the constraint key (count starts at 1)

position_in_unique_constraint

cardinal_number

For a foreign-key constraint, ordinal position of the referenced column within its unique constraint (count starts at 1); otherwise null