SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9739057032cd0d859730a9c2d630b190bc007acf44cc22ecd39f24e691d12c09' 
  AND token = 'e4d3zrwJJSKplGo6cIbRebziELCEpVeIbxHIcANc9IE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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