Execute the following Microsoft SQL Server T-SQL script to list all constraint in the database by schema, by table, by column:

use AdventureWorks;

select

      c.TABLE_SCHEMA,

      c.TABLE_NAME,

      c.COLUMN_NAME,

      c.CONSTRAINT_NAME

from INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE as c

union all

select

      s.name,

      o.name,

      c.name,

      dc.name

  from sys.default_constraints as dc

  join sys.objects as o

    on o.object_id = dc.parent_object_id

  join sys.columns as c

    on c.object_id = o.object_id

   and c.column_id = dc.parent_column_id

  join sys.schemas as s

    on s.schema_id = o.schema_id

  order by TABLE_SCHEMA, TABLE_NAME, COLUMN_NAME, CONSTRAINT_NAME

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SQL SERVER – 2005 – List All The Constraint of Database – Find Primary Key and Foreign Key Constraint in Database