Summary of common operations of Postgresql ALTER statement _postgresql

PostgreSQL version: Psql (9.3.4)

1. Add a column

Copy Code code as follows:

ALTER TABLE table_name ADD column_name datatype;

2, delete a column

Copy Code code as follows:

ALTER TABLE table_name DROP column_name;

3, change the data type of the column

Copy Code code as follows:

ALTER TABLE TABLE_NAME ALTER COLUMN_NAME TYPE datatype;

4, the table renaming

Copy Code code as follows:

ALTER TABLE table_name RENAME to new_name;

5, change the name of the column

Copy Code code as follows:

ALTER TABLE table_name RENAME column_name to New_column_name;

6, the field is not null setting

Copy Code code as follows:

ALTER TABLE table_name ALTER COLUMN_NAME {set| DROP} not NULL;

7. Add default to Column

Copy Code code as follows:

ALTER TABLE table_name ALTER COLUMN_NAME SET DEFAULT expression;