underbell

var unique_check = {};for(var i = 0 ; i < array.length ; i++) {if(typeof unique_check[array[i]] == "undefined") {unique_check[array[i]] = 0;}else {alert("중복");return;}}

analyze table TABLE_NAME compute statistics; select NUM_ROWS*AVG_ROW_LEN from user_tableswhere table_name = 'TABLE_NAME';

simpleDateFormat 쓰레드 락 걸릴 때 있다Calendar 역시 static은 쓰레드 락 걸린다FastDateFormat 쓰자 Format sdf = FastDateFormat.getInstance("yyyyMMddHHmmss", Locale.getDefault());String currDate = sdf.format(new Date()); log.debug("yyyyMMddHHmmss : " + currDate); http://stackoverflow.com/questions/6840803/simpledateformat-thread-safetyhttp://devday.tistory.com/entry/SimpleDateFormat%EA%B3%BC-Thread-Safety