SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '538706328911929ecb1697650446ae4fec9a477950d2e67174e3f7eddafbf8bd' 
  AND token = 'hP9quxMsRlolMx32aE161xcrWTaSO7Pb32coR9/RA+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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