SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df554562bd619e343b329d9cf72667358a51708aa8fa97ed66940e92c460005f' 
  AND token = 'zc2mv1Jz0pk5zhgwOXqlTPA5VN5RUFRciet8hlhZAww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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