Language Usage / DML & SQL / General
Never use SELECT * in a (sub-)query that selects directly from tables or views

fromSonarQube

Columns to be read with a "SELECT" statement should be clearly defined

SELECT * should be avoided because it releases control of the returned columns and could therefore lead to errors and potentially to performance issues.

Noncompliant Code Example

DECLARE  myvarCHAR;BEGINSELECT* INTO myvarFROM DUAL; END;

Compliant Solution

DECLARE  myvarCHAR;BEGINSELECT dummy INTO myvarFROM DUAL;END;

Exceptions

Wrapper queries using ROWNUM are ignored.

SELECT*FROM (SELECT fname, lname, deptIdFROM employeeORDER BY salary  )WHERE rownum<=10