Updating multiple rows at a time in sql server ratings of online dating sites

Note Any call to OPENDATASOURCE, OPENQUERY, or OPENROWSET in the FROM clause is evaluated separately and independently from any call to these functions used as the target of the update, even if identical arguments are supplied to the two calls.

The results of an UPDATE statement are undefined if the statement includes a FROM clause that is not specified in such a way that only one value is available for each column occurrence that is updated, that is if the UPDATE statement is not deterministic. Modifying a text, ntext, or image column with UPDATE initializes the column, assigns a valid text pointer to it, and allocates at least one data page, unless the column is being updated with NULL.

For example, in the UPDATE statement in the following script, both rows in USE Adventure Works2012; GO IF OBJECT_ID ('dbo. To replace or modify large blocks of text, ntext, or image data, use WRITETEXT or UPDATETEXT instead of the UPDATE statement.

Common table expressions can also be used with the SELECT, INSERT, DELETE, and CREATE VIEW statements.

For more information, see WITH common_table_expression (Transact-SQL). For information about table hints, see Table Hints (Transact-SQL).

Specifies the condition to be met for the rows to be updated.

The search condition can also be the condition upon which a join is based.For more information, see The Transaction Log (SQL Server).The Database Engine converts a partial update to a full update when the UPDATE statement causes either of these actions: are specified in bytes for varbinary and varchar data types and in characters for the nvarchar data type.For example, a partial update of a varchar(max) column might delete or modify only the first 200 characters of the column, whereas a full update would delete or modify all the data in the column. WRITE updates that insert or append new data are minimally logged if the database recovery model is set to bulk-logged or simple.Minimal logging is not used when existing values are updated.Any characters not found in this code page are lost.

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