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Changing data using update – Sybase 12.4.2 User Manual

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Changing data using UPDATE

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The Append_Load option applies to

LOAD

,

INSERT...SELECT

, and

INSERT...VALUES

statements.

For more information on versioning see Chapter 8, “Transactions and
Versioning”.

Changing data using UPDATE

You can use the

UPDATE

statement, followed by the name of the table or view,

to change single rows, groups of rows, or all rows in a table. As in all data
modification statements, you can change the data in only one table or view at
a time.

The

UPDATE

statement specifies the row or rows you want changed and the

new data. The new data can be a constant or an expression that you specify or
data pulled from other tables.

If an

UPDATE

statement violates an integrity constraint, the update does not

take place and an error message appears. For example, if one of the values
being added is the wrong data type, or if it violates a constraint defined for one
of the columns or data types involved, the update does not take place.

UPDATE syntax

See the Adaptive Server IQ Reference Manual for complete

UPDATE

syntax. A

simplified version of the syntax is:

UPDATE

table-name

SET

column_name = expression

WHERE

search-condition

If the company Newton Ent. (in the customer table of the sample database) is
taken over by Einstein, Inc., you can update the name of the company using a
statement such as the following:

UPDATE customer

SET company_name = ’Einstein, Inc.’

WHERE company_name = ’Newton Ent.’

You can use any condition in the WHERE clause. If you are not sure how the
company name was entered, you could try updating any company called
Newton, with a statement such as the following:

UPDATE customer

SET company_name = ’Einstein, Inc.’

WHERE company_name LIKE ’Newton%’