SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '211074222a3203aabe66a0f92df34792fc7c914e0fad5db69e2d0d6de6ecdb9c' 
  AND token = 'FD0FKiQG3INywrH4Osnjof8X49iODfcd0+wBif7MpPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}