PostgreSQL ALTER common statements

1. Add a column

ALTER TABLE table_name ADD column_name datatype;

2. Delete a column

ALTER TABLE table_name DROP column_name;

3. Change the data type of a column

ALTER TABLE TABLE_NAME ALTER COLUMN_NAME TYPE datatype;

4. Renaming a table

ALTER TABLE table_name RENAME to new_name;

5, change the name of the column

ALTER TABLE table_name RENAME column_name to New_column_name;

6, the NOT NULL setting for the field

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

7. Add default to Columns

ALTER TABLE table_name ALTER COLUMN_NAME SET DEFAULT expression;

PostgreSQL ALTER common statements