The Optimization Process - Inside the SQL Server Query Optimizer - page 152

SELECT c . CustomerID , COUNT (*)
FROM Sales . Customer c JOIN Sales . SalesOrderHeader o
ON c . CustomerID = o . CustomerID
GROUP BY c . CustomerID

Listing 5-9.

As shown in the following output, 17 transformation rules were exercised during the
optimization process.

Name Promised

AppIdxToApp

0

EnforceSort

23

GbAggBeforeJoin

4

GbAggToHS

8

GbAggToStrm

8

GenLGAgg

2

GetIdxToRng

0

GetToIdxScan

4

GetToScan

4

ImplRestrRemap

3

JNtoHS

6

JNtoIdxLookup

6

JNtoSM

6

JoinCommute

2