How do I view table constraints?

You have to query the data dictionary, specially the USER_CONS_COLUMNS view to see the table columns and the corresponding constraints like this:

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

How can I view table constraints in SQL?

Use the view table_constraints in the information_schema schema. The column table_name gives you the name of the table in which the constraint is defined, and the column constraint_name contains the name of the constraint.

How do I find unique constraints in db2?

How can I list the DB2 table columns and unique constraints?

  1. –Method 1 – query syscat.columns.
  2. select colname from syscat.columns where tabname= ‘ADDRESS’
  3. –Method 2 – use the describe command.
  4. describe table dbo.address.
  5. –Method 3 –use db2look.
  6. db2look -e –d dbname –t tablename.

What are the constraints in db2?

The constraints types are:

  • NOT NULL.
  • Unique.
  • Primary key.
  • Foreign Key.
  • Check.
  • Informational.

What are constraints in SQL table?

SQL constraints are used to specify rules for the data in a table. Constraints are used to limit the type of data that can go into a table. This ensures the accuracy and reliability of the data in the table. If there is any violation between the constraint and the data action, the action is aborted.

How do you create a constraint in Db2?

You add informational constraints using the CREATE TABLE or ALTER TABLE statement when you specify the NOT ENFORCED option on the DDL. Restriction: After you define informational constraints on a table, you can only alter the column names for that table after you remove the informational constraints.

What is unique index in Db2?

Db2 uses unique indexes to ensure that no identical key values are stored in a table. When you create a table that contains a primary key or a unique constraint, you must create a unique index for the primary key and for each unique constraint.

What are the 3 three database constraints?

DEFAULT Constraint − Provides a default value for a column when none is specified. UNIQUE Constraint − Ensures that all values in a column are different. PRIMARY Key − Uniquely identifies each row/record in a database table. FOREIGN Key − Uniquely identifies a row/record in any of the given database table.

What are 5 types of constraints?

An informational constraint is an attribute of a certain type of constraint, but the attribute is not enforced by the database manager.

  • NOT NULL constraints.
  • Unique constraints.
  • Primary key constraints.
  • (Table) Check constraints.
  • Foreign key (referential) constraints.
  • Informational constraints.

Where can I find constraints in SQL Server?

Constraints in SQL Server can be defined at the column level, where it is specified as part of the column definition and will be applied to that column only, or declared independently at the table level.

How do I view constraints in SQL Server management Studio?

Click on the plus symbol beside the table name. Folders for the columns, indexes and constraints etc will appear. Click on the plus beside the Constraints folder and any constraints on the table will be displayed.