SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eac6990092f7804bcd6cad2630c68fbe5fbe2f86dbc48a89847a71ea90549f25' 
  AND token = 'Yvzon0E4sxjw/XkXd+xjkvUU0wVWTLFDGE+wZRbeiVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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