SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2899b7ed927cc7064827b160ff1664c0398591c723d72c8c495dcc5670ff85d' 
  AND token = '7H8Rp/9MZwz3sQhPGg4fflWBiYfPO9uwu+6NFbDBR1c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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