Use Existing Column Values in SET Clause in Oracle

Q

How To Use Existing Values in UPDATE Statements in Oracle?

✍: FYIcenter.com

A

If a row matches the WHERE clause in a UPDATE statement, existing values in this row can be used in expressions to provide new values in the SET clause. Existing values are represented by columns in the expressions. The tutorial exercise below shows a good example:

UPDATE fyi_links SET id = 1000 + id, counts = id*2 
  WHERE id >= 250;
3 rows updated.

SELECT * FROM fyi_links WHERE id >= 250;
   ID URL                  NOTES         COUNTS CREATED
----- -------------------- ------------ ------- ---------
 1250 Retail Sales.com     Wrong URL        500 07-MAY-06
 1260 Recruiting.com       Wrong URL        520 07-MAY-06
 1270 Payroll.com          Wrong URL        540 07-MAY-06

This statement increased values in the id column by 1000.

⇒ Use Values from Other Tables in UPDATE in Oracle

⇐ Update Values on Multiple Rows in Oracle

⇑ Understanding SQL DML Statements for Oracle

⇑⇑ Oracle Database Tutorials

2020-01-21, 2810🔥, 0💬

Insert Multiple Rows with 1 INSERT Statement in Oracle
How To Insert Multiple Rows with One INSERT Statement in Oracle? If you want to insert multiple rows with a single INSERT statement, you can use a subquery instead of the VALUES clause. Rows returned from the subquery will be inserted the target table. The following tutorial exercise gives a good ex... 2020-01-29, 3540🔥, 0💬

Delete Multiple Rows from a Table in Oracle
How To Delete Multiple Rows from a Table in Oracle? You can delete multiple rows from a table in the same way as deleting a single row, except that the WHERE clause will match multiple rows. The tutorial exercise below deletes 3 rows from the fyi_links table: SELECT * FROM fyi_links WHERE id &gt... 2020-01-04, 3470🔥, 0💬

Omit Columns in INSERT Statements in Oracle
How To Omit Columns with Default Values in INSERT Statement in Oracle? If you don't want to specify values for columns that have default values, or you want to specify values to columns in an order different than how they are defined, you can provide a column list in the INSERT statement. If a colum... 2020-01-29, 3176🔥, 0💬

Delete an Existing Row from a Table in Oracle
How To Delete an Existing Row from a Table in Oracle? If you want to delete an existing row from a table, you can use the DELETE statement with a WHERE clause to identify that row. Here is good sample of DELETE statements: INSERT INTO fyi_links (url, id) VALUES ('http://www.myspace.com', 301); 1 row... 2020-01-04, 3160🔥, 0💬

Use Values from Other Tables in UPDATE in Oracle
How To Use Values from Other Tables in UPDATE Statements in Oracle? If you want to update values in one with values from another table, you can use a subquery in the SET clause. The subquery should return only one row for each row in the update table that matches the WHERE clause. The tutorial exerc... 2020-01-21, 2977🔥, 0💬

in Oracle
How To Delete All Rows from a Table in Oracle? 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 exa... 2020-01-04, 2886🔥, 0💬

Use Existing Column Values in SET Clause in Oracle
How To Use Existing Values in UPDATE Statements in Oracle? If a row matches the WHERE clause in a UPDATE statement, existing values in this row can be used in expressions to provide new values in the SET clause. Existing values are represented by columns in the expressions. The tutorial exercise bel... 2020-01-21, 2811🔥, 0💬

Update Values on Multiple Rows in Oracle
How To Update Values on Multiple Rows in Oracle? If the WHERE clause in an UPDATE matches multiple rows, the SET clause will be applied to all matched rows. This rule allows you to update values on multiple rows in a single UPDATE statement. Here is a good example: UPDATE fyi_links SET counts = 9, n... 2020-01-21, 2795🔥, 0💬

Specify Default Values in INSERT Statements in Oracle
How To Specify Default Values in INSERT Statement in Oracle? If a column is defined with a default value in a table, you can use the key word DEFAULT in the INSERT statement to take the default value for that column. The following tutorial exercise gives a good example: INSERT INTO fyi_links VALUES ... 2020-01-29, 2791🔥, 0💬

All rights in the contents of this web site are reserved by the individual author. fyicenter.com does not guarantee the truthfulness, accuracy, or reliability of any contents.