How Do You Drop A Table If It Exists In SQL?

Does Drop Table remove constraints?

DROP TABLE removes tables from the database.

DROP TABLE always removes any indexes, rules, triggers, and constraints that exist for the target table.

However, to drop a table that is referenced by a view or a foreign-key constraint of another table, CASCADE must be specified..

Do we need to drop table variable in SQL Server?

We do not require dropping the table variable. As mentioned earlier, the scope of the table variable is within the batch. The scope of it lasts at the end of the batch or procedure.

What is Delete command?

Summary. The delete command is used to remove data that is no longer required from a table. The “WHERE clause” is used to limit the number of rows affected by the DELETE query.

How do I drop a #tmp table in SQL?

Using the DROP TABLE command on a temporary table, as with any table, will delete the table and remove all data. In an SQL server, when you create a temporary table, you need to use the # in front of the name of the table when dropping it, as this indicates the temporary table.

What is difference between drop and delete command?

DELETE is a Data Manipulation Language command, DML command and is used to remove tuples/records from a relation/table. Whereas DROP is a Data Definition Language, DDL command and is used to remove named elements of schema like relations/table, constraints or entire schema.

How do you drop a table in a database?

To delete an entire table including all of its rows, issue the drop table command followed by the tablename. drop table is different from deleting all of the records in the table. Deleting all of the records in the table leaves the table including column and constraint information.

Are temp tables required to drop a stored procedure?

2 Answers. I will talk about this in much more detail in my next post, but the key point is that CREATE TABLE and DROP TABLE do not create and drop temporary tables in a stored procedure, if the temporary object can be cached. … This means that statistics from a previous execution remain when the procedure is next called …

Why use truncate instead of delete?

TRUNCATE TABLE is faster and uses fewer system resources than DELETE , because DELETE scans the table to generate a count of rows that were affected then delete the rows one by one and records an entry in the database log for each deleted row, while TRUNCATE TABLE just delete all the rows without providing any …

What is drop table if exists?

Description. The DROP TABLE statement deletes the specified table, and any data associated with it, from the database. The IF EXISTS clause allows the statement to succeed even if the specified tables does not exist.

What is MySQL temporary table?

In MySQL, a temporary table is a special type of table that allows you to store a temporary result set, which you can reuse several times in a single session. A temporary table is very handy when it is impossible or expensive to query data that requires a single SELECT statement with the JOIN clauses.

Does drop table delete table structure?

The DROP TABLE is another DDL (Data Definition Language) operation. But it is not used for simply removing data from a table; it deletes the table structure from the database, along with any data stored in the table. This removes all data in the table product and the structure of the table. …

Which is faster truncate or drop?

TRUNCATE is a DDL(Data Definition Language) command. It is used to delete all the tuples from the table. Like the DROP command, the TRUNCATE command also does not contain a WHERE clause. The TRUNCATE command is faster than both the DROP and the DELETE command.

How do you check if a table exists in SQL?

To check if a table exists in SQL Server, you can use the INFORMATION_SCHEMA. TABLES table. You can use this table with an IF THEN clause do determine how your query responds whether or not a table exists.

Do I need to drop temp tables?

No… you don’t need to drop temp tables. That notwithstanding, I tend to do a conditional drop at the beginning of a sproc and it has nothing to do with any effect on the spoc. Rather, they are an artifact from development and testing prior to conversion to a stored procedure.