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SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = 'b1b15538af70c9823a0e65c8b836bd261331b771f37ae46922c2bc26354b3fbd' 
  AND token = 'v8tQBxoJlTIvIC3vBocznRsQ9lTTv+Kf3sMSChSqE9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.01465

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}