Avoid Programs with SELECT * statement (RPG400) | CAST Appmarq

Avoid Programs with SELECT * statement (RPG400)

CRITICAL

Rule Definition
A query that retrieves all columns of a table with a SELECT * can potentially be the source of important performance problems: Such performance problems may arise when the execution of the query returns a large result sets (many row with all the columns may then become a huge amount of data to transport over the network). Thus optimzer module can't provide a correct execution. Also, when using such queries, one cannot control how the columns will be ordered and returned to the client. This can lead to important data inconsistencies and thus stability issues.

Remediation
Review the design of the query to select only useful Columns

Violation Code Sample
C/EXEC SQL      
C+ select *    // Quality Rule Violation  
C+ from sample_table;    
C/END-EXEC
Fixed Code Sample
Remediation for Sample:
C/EXEC SQL      
C+ select column1,column2 ...     
C+ from sample_table;    
C/END-EXEC

Related Technologies

Health Factor

  Total Quality Index


Technical Criterion
Efficiency - SQL and Data Handling Performance

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Benchmark Statistics

Global Compliance

nan%

Total Violations
0
Total Opportunities
0
Average Violations / App.
nan
The compliance score represents 1 minus the ratio between the number of times a rule has been violated compared to the number of opportunities in a set of applications that the rule could have been violated.

Industry Insights

Utilities

100.00%