Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c847b176759f8dd4c70002414118fe4738ae2d02e0be5878ce34bb8d893a4780' 
  AND token = 'mPUfP3Fb3ztmKudCKGpqAPZXxRVO80+Le3PwJXCr+Qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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