The query return different execution plan using this simple query
SELECT DLS FROM MFG_LotMoveData WHERE lot = 'K00747'. The query plan like below. There are 1 index with the name Lot but the index was unused. This will makes deadlock occured.
Sometimes the query plan return Index seek with key lookup. Which will not makes deadlock occured.
May I know why the execution plan are different from time to time even with same index created?