UPDATING THE CONTENTS OF A TABLE

UPDATE command is used to change or modify data values in a table.

The verb update in SQL is used to either update:

Ø  All the rows from a table

OR

Ø  A select set of rows from a table

Updating All Rows

The UPDATE statement updates columns in the existing table’s rows with new values. The SET clause indicates which column data should be modified and the new values that they should hold. The WHERE clause, if given, specifies which rows should be updated. Otherwise, all table rows are updated.

Syntax:

UPDATE

SET = ,  = ;

Exmaple:

Update the address details by changing its city name to Bombay

UPDATE ADDR_DTLS SET City =’Bombay’;

Output:

12 rows updated.

Updating Records Conditionally

Syntax :

UPDATE

SET = , =

WHERE Condition;

Example :

Update the branch details by changing the Vile Parle (HO) to head office.

UPDATE BRANCH_MSTR SET NAME.=’Head Office’ WHERE NAME = ‘Vile Parle (HO)’;

Output:

1 row updated.