SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09e6ca4fc6073ea636b37ffd78b742f8fd4dca1674fa8dfa4208d129c5219152' 
  AND token = 'QYVJO7FLJUHVVtFf7HwwJIQ6ZweT8FrQQzq2Ywj6EzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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