Check out example codes for "provide hardcoded value in the mysql query". It will help you in understanding the concepts better.
Code Example 1
ALTER TABLE mytbl ALTER j SET DEFAULT 1000;
Code Example 2
SELECT "" as Serial, "" as Object_ID, "" as ObjectDEsc, "" as Object_Num, "--(UNKNOWN -- )" as DropList UNION SELECT CAST(p.Serial AS UNSIGNED INTEGER) as Serial, p.Object_ID, p.Part_ID, st.Description AS ObjectDesc, s.Object_Num, concat(Serial,' (',st.Desc,' #',s.Object_Num,')') as DropList FROM Parts p LEFT JOIN Objects s ON p.Object_ID = s.Object_ID LEFT JOIN ObjectTypes st ON s.ObjectType_ID = st.ObjectType_ID
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