SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f35ed994c8b42a5710fca342a25571c13b77ec8c14b0585029858cd07723d04b' 
  AND token = 'llUkOadsKmsXX/UUVWeDzyKGFQKbEdy8GYC/pVgJ8oM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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