SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebde320ada7d991336fbb69f160fef4a7e23800c7acfd1422ab93ce8f1640f73' 
  AND token = '7i8DxVIli9J/BeKy1BTLhjb65zYv/gXlma6ghHEDTkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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