Notice that you need to add a comma ( ,) after each DROP COLUMN clause.
MYSQL DELETE COLUMN TO TABLE CODE
Code language: SQL (Structured Query Language) ( sql ) If you want to drop multiple columns of a table in a single command, you use multiple DROP COLUMN clause like this: ALTER TABLE table_name
In this form, if you remove a column that does not exist, PostgreSQL will issue a notice instead of an error.
To remove a column only if it exists, you can add the IF EXISTS option as follows: ALTER TABLE table_nameĭROP COLUMN IF EXISTS column_name Code language: SQL (Structured Query Language) ( sql ) If you remove a column that does not exist, PostgreSQL will issue an error. In this case, you need to add the CASCADE option to the DROP COLUMN clause to drop the column and all of its dependent objects: ALTER TABLE table_nameĭROP COLUMN column_name CASCADE Code language: SQL (Structured Query Language) ( sql ) If the column that you want to remove is used in other database objects such as views, triggers, stored procedures, etc., you cannot drop the column because other objects are depending on it. When you remove a column from a table, PostgreSQL will automatically remove all of the indexes and constraints that involved the dropped column.
To drop a column of a table, you use the DROP COLUMN clause in the ALTER TABLE statement as follows: ALTER TABLE table_nameĭROP COLUMN column_name Code language: SQL (Structured Query Language) ( sql ) Introduction to PostgreSQL DROP COLUMN clause
MYSQL DELETE COLUMN TO TABLE HOW TO
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