PostgreSQL Constraints 38 codes

1 Add and DROP DEFAULT

2 Add PRIMARY KEY in table creation

3 Add primary key in table create statement

4 Adding a Constraint

5 Adding a constraint to an existing table

6 Adding constraints (FOREIGN KEY) to a table

7 ALTER TABLE employee ADD CONSTRAINT some_nameForConstaint UNIQUE (id)

8 ALTER TABLE employee ADD FOREIGN KEY (group_id) REFERENCES product_groups

9 ALTER TABLE employee ALTER COLUMN id DROP NOT NULL

10 ALTER TABLE employee ALTER COLUMN name SET NOT NULL

11 Assign your own name for a unique constraint

12 Changing a Columns Default Value

13 Create FOREIGN KEY

14 CREATE OR REPLACE RULE

15 Create table with default column value

16 Define foreign key for a table

17 Implicit index is created when creating a table for a primary key

18 Indicate one column as the primary key column

19 Null column

20 PRIMARY KEY will create implicit index

21 Primary key with check option

22 Primary keys constrains more than one column

23 Reference two two columns as foreign key column

24 Removing a Constraint

25 Specify CONSTRAINT

26 Specify not null constaint for column

27 Specifying range check in table creation

28 Specifying the column relation

29 Specifying the unique column using Unique function

30 Specifying three check constaints to a table

31 Specifying two constaint for a single table

32 To remove any default value

33 Unique and not null column

34 Unique constraint refers to a group of columns, the columns are listed separated by commas

35 Unique Constraints

36 Use boolean operator in check statement

37 Use sequence value as a primary key

38 Using foreign keys