Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f7776449744fbc00f3cd074459998af573b9057b20364eac5bb58ec05c7bf3f0' 
  AND token = 'tMv9YPVBBn+c/jXwhBkDe5cNHhAfnw+Si3rAC1uud0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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