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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce3abcb9362ca29a9a6e56009bad06027081a65a351de404b5d2a7d975a4f7f3' 
  AND token = 'PBhg0vTBx+sPZxSjTl3x8Ty7ytth7MFf3B/TRM2UiwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}