SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fecfe31ffbb12b8545553eb4fd096eff5333612bb522cfdcae8fc32ae0cd6a78' 
  AND token = 'Oqhc5EqxWkNA6hixruFvvs79aFA96HFdTkKTbirWF3E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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