SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c80370ec2218d109663858013d6b7cfc6478021f7a2efb83701826f9fd6fa07' 
  AND token = 'VzY0NjJcOZ++jqF7biYFITCn2xK9/eylyyfNRwGHWIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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