SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb3aa0c545ea9c2f2e7a241cc412ed1c1fcd3f8865ecdd0c73f905496f6179c1' 
  AND token = 'BcsaqVAVKNnLzv+ubYR7E6i/hwK3f5ALxjBlkHwS6WA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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