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
Technical Criterion
Efficiency - SQL and Data Handling Performance
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