How can we see existing constraints in a table?

How can we see existing constraints in a table?

1 Answer

1. SELECT * FROM user_cons_columns. WHERE table_name = ”;
2. SELECT * FROM user_constraints. WHERE table_name = ” AND constraint_name = ”;
3. all_cons_columns.
4. all_constraints.
5. AND owner = ”

Which table stores constraint information?

In SQL Server the data dictionary is a set of database tables used to store information about a database’s definition. One can use these data dictionaries to check the constraints on an already existing table and to change them(if possible).

How do I view all constraints in SQL?

Columns

1. constraint_name – name of the constraint in the database.
2. table – schema and table name constraint is defined for.
3. column_name – name of the column for column-level check constraints, null for table-level check constraints.
4. definition – SQL expression that defines this check constraint.
5. status – constraint status.

How to display all constraints on a table?

To display all constraints on a table, you can try any of the following methods − Method 1 − Using SHOW command. You can check with the help of show command. The syntax is as follows − SHOW CREATE TABLE yourTableName; Method 2 − Using information.schema. You can use information.schema. The syntax is as follows −

How to find default constraints in a database?

The script below lists all the default constraints and the default values for the user tables in the database in which it is being run: If you want to get a constraint by the column or table names, or you want to get all the constraints in the database, look to other answers.

Which is the best schema to use in SQL Server?

INFORMATION_SCHEMA seems like the best choice for this kind of task because it is cross-platform, but if the information isn’t available one should use the object catalog views (sys.*) instead of system table views, which are deprecated in SQL Server 2005 and later. Below is pretty much the same as @user186476’s answer.