How do I delete multiple rows in db2?
- First, specify the name of the table from which you want to delete data.
- Second, use a condition in the WHERE clause to specify which rows to delete. All rows that cause the condition to evaluate to true will be deleted.
How delete all rows from table in SQL?
To delete every row in a table:
- Use the DELETE statement without specifying a WHERE clause. With segmented table spaces, deleting all rows of a table is very fast.
- Use the TRUNCATE statement. The TRUNCATE statement can provide the following advantages over a DELETE statement:
- Use the DROP TABLE statement.
How do I delete a table in db2?
- To drop a table, use a DROP TABLE statement. The following statement drops the table that is called DEPARTMENT: DROP TABLE DEPARTMENT.
- To drop all the tables in a table hierarchy, use a DROP TABLE HIERARCHY statement. The DROP TABLE HIERARCHY statement must name the root table of the hierarchy to be dropped.
How do you quickly delete a row in SQL?
How to Delete Millions of Rows Fast with SQL
- Removing all the rows fast with truncate.
- Using create-table-as-select to wipe a large fraction of the data.
- Dropping or truncating partitions.
- Using a filtered table move.
How do I delete a row in mainframe?
To delete one or more lines:
- Type D in the line command field of the line to be deleted. If you also want to delete one or more lines that immediately follow this line, type a number greater than 1 after the D command.
- Press Enter. The line or lines are deleted.
Is Db2 secure?
DB2 security is set through a security plan, implemented through privilege and authority management, and reinforced through the audit of accesses to protected data.
How do I delete a view in Db2?
Introduction to DROP VIEW statement In this syntax, you just need to specify the name of the view that you want to delete in the DROP VIEW clause. Once you delete the view, Db2 will mark all views that depend on the deleted view inoperative.
How do I uninstall run faster?
For single user optimization
- Hint a TABLELOCK.
- Remove indexes not used in the delete then rebuild them afterward.
- Batch using something like SET ROWCOUNT 20000 (or whatever, depending on log space) and loop (perhaps with a WAITFOR DELAY ) until you get rid of it all ( @@ROWCOUNT = 0 )
How to delete rows in a table in DB2?
Summary: in this tutorial, you will learn how to delete one or more rows in a table using the Db2 DELETE statement. The DELETE statement allows you to delete one or more rows from a table. The following illustrates the syntax of the DELETE statement: First, specify the name of the table from which you want to delete data.
Which is an example of the DELETE statement in DB2?
The following example uses a condition in the WHERE clause to delete multiple rows from the lists table. Db2 issued the following message indicating that 3 rows have been deleted successfully. 3 rows deleted. The following example uses the DELETE statement to remove all rows from the lists table: The output is as follows:
How to limit number of rows in DB2?
Introduction to Db2 LIMIT clause. The LIMIT clause allows you to limit the number of rows returned by the query. The LIMIT clause is an extension of the SELECT statement that has the following syntax: SELECT select_list FROM table_name ORDER BY sort_expression LIMIT n [ OFFSET m];
What happens if you skip the where clause in DB2?
The WHERE clause is optional. If you skip it, the DELETE statement will remove all rows from the target table. If no row satisfies the condition, the DELETE statement just does nothing. Typically, a table is associated with another table via a relationship: one-to-one, one-to-many, or many-to-many.