How To Delete All Rows a Table

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Q

How To Delete All Rows a Table? - Oracle DBA FAQ - Understanding SQL DML Statements

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A

If you want to delete all rows from a table, you have two options:

Use the DELETE statement with no WHERE clause.
Use the TRUNCATE TABLE statement.

The TRUNCATE statement is more efficient the DELETE statement. The tutorial exercise shows you a good example of TRUNCATE statement:

SELECT COUNT(*) FROM fyi_links;
  COUNT(*)
----------
         3

TRUNCATE TABLE fyi_links;
Table truncated.

SELECT COUNT(*) FROM fyi_links;
  COUNT(*)
----------
         0

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