In this tutorial, you have learned how to use the SQL Server DROP TABLE statement to remove one or more tables from a database. If you use a single DROP TABLE statement to remove both tables, the referencing table must be listed first as shown in the query below: DROP TABLE procurement.suppliers, procurement.supplier_groups In this case, you have to drop the foreign key constraint in the suppliers table or the suppliers table first before removing the supplier_groups table. To delete this table, you must drop the referencing foreign key constraint or referencing table first. SQL Server does not allow you to delete a table that is referenced by a foreign constraint. SQL Server issued the following error: Could not drop object 'procurement.supplier_groups' because it is referenced by a FOREIGN KEY constraint. Drop Table Command for SQL Server 2014 and prior versions. Let’s try to drop the supplier_groups table: DROP TABLE procurement.supplier_groups The following statement creates two new tables named supplier_groups and suppliers in the procurement schema: CREATE SCHEMA procurement ĬREATE TABLE procurement.supplier_groups (įOREIGN KEY ( group_id) REFERENCES procurement.supplier_groups ( group_id) To remove the delivery table, you use the following statement: DROP TABLE livery Ĭode language: SQL (Structured Query Language) ( sql ) C) Drop a table with a foreign key constraint example The following statement creates a new table named delivery in the sales schema: CREATE TABLE livery ( Because it uses the IF EXISTS clause, the statement executes successfully with no table deleted. In this example, the revenues table does not exist. The following statement removes a table named revenues in the sales schema: DROP TABLE IF EXISTS sales.revenues Let’s see some examples of using the SQL Server DROP TABLE statement. Table_name_n SQL Server DROP TABLE examples SQL Server allows you to remove multiple tables at once using a single DROP TABLE statement as follows: DROP TABLE table_name_1, Therefore, to explicitly drop these dependent objects, you must use the DROP VIEW and DROP PROCEDURE statement. Moreover, SQL Server does not explicitly drop the views and stored procedures that reference the dropped table.
When SQL Server drops a table, it also deletes all data, triggers, constraints, permissions of that table. The IF EXISTS clause conditionally removes the table if it already exists. If you remove a table that does not exist, you will get an error. The IF EXISTS clause has been supported since SQL Server 2016 13.x. Third, use IF EXISTS clause to remove the table only if it exists.If you skip it, the DROP TABLE statement will drop the table in the currently connected database. Second, specify the name of the database in which the table was created and the name of the schema to which the table belongs.First, specify the name of the table to be removed.To do this, you use the following DROP TABLE statement: DROP TABLE table_name Ĭode language: SQL (Structured Query Language) ( sql ) Sometimes, you want to remove a table that is no longer in use. Same has to be done for USER, VIEW and so on.Summary: in this tutorial, you will learn how to use the SQL Server DROP TABLE statement to remove one or more tables from a database. SQL> exec for f in (select 'drop table "'||table_name||'"' cmd from user_tables where table_name='T')loop execute immediate f.cmd end loopĪ bit easier to read. Select 'drop table "'||table_name||'"' cmd
So I check the dictionary, put a command to drop in the sqlplus buffer if a table exists, then run that command first.ĭef cmd="select 'OK: Table does not exist' from dual" PL/SQL is also possible but it generated different error messages (ORA-06512: at line 1) and different feedback (PL/SQL procedure successfully completed.) If you use IF EXISTS option, then SQLite removes the table only if the table exists, otherwise, it. In the Oracle database, I have created my own droptableifexists script. If you remove a non-existing table, SQLite issues an error. ORA-00933: SQL command not properly ended
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