SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04dd9e23bb6abdd46db2085a2e90be10d46c0182ac6194e368c3342f01f4ed43' 
  AND token = 'fGpV75nvKLkxFV7VyDmbcvtfX577ioanRyxMqtMBvrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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