SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '704daf156e0f5f51b5e58c16d35c6fb76560d5d02ba0d42c53f32deca8f84fcd' 
  AND token = 'ghldBWfaSsTxvKXKAU8QaufCG/4z10YaPmToZCywXWY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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