Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a90083a443701b2db65ef3d4f3f3a9f673a3a86cb6e37e71b85ffffa1424375b' 
  AND token = 'MEBBiJxIFl6T/8r+UOvLsUe3cmrl1j7MMb4szh3ICCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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