SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c17563179755d19743183eb05d76070d1ff19d6c663c6415bb570b32ac84db98' 
  AND token = 'wTFNeuNFXvHjtBHXE+NTzIpXkHdo28zT94vCQoEOWfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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