Identifying Search Arguments
A SARG is defined as a WHERE
clause that compares a column to a constant. The format of a SARG is as follows:
Column operator constant_expression [and...]
SARGs provide a way for the Query Optimizer to limit the rows searched to satisfy a query. The general goal is to match a SARG with an index to avoid a table scan. Valid operators for a SARG are =, >, <, >=, and <=, BETWEEN
, and LIKE
. Multiple SARGs can be combined with the AND
clause. (A single index might match some or all of the SARGs AND
ed together.) Following are examples of SARGs:
flag = 7
salary > 100000
city = 'Saratoga' and ...
Get Microsoft SQL Server 2014 Unleashed now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.