CRITICAL
Rule Definition
Having complex queries in Programs can cause performance problems.
Remediation
Try to reduce the complexity of queries or the number of complex queries
Violation Code Sample
SELECT *
FROM HumanResources.Employee E
WHERE E.EmployeeID = ( SELECT EA.EmployeeID
FROM HumanResources.EmployeeAddress EA
WHERE EA.EmployeeID = E.EmployeeID)
Fixed Code Sample
Use join instead:
SELECT *
FROM HumanResources.Employee E
INNER JOIN HumanResources.EmployeeAddress EA ON E.EmployeeID = EA.EmployeeID
Related Technologies
Technical Criterion
Efficiency - SQL and Data Handling Performance
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