SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '933ebfc5fd0deae41cf74c12f1913e0284d18d0687c7bbf25750f4bae875756c' 
  AND token = 'qx9O3/LYaVUP9H4s98HOVsIoXORBWcoQn2TF4FvebTE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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