FIRST DAY

1 개요

FIRST_DAY

first day of month

first_of_month

• test set

"2011-11-11" → "2011-11-01"

2 Bash

INPUT=2011-11-11
OUTPUT="${INPUT:0:7}-01"
echo $OUTPUT

3 PHP

function first_of_month($day) {
  return substr($day, 0, 7).'-01';
}

4 SQL

4.1 MySQL

SELECT CONCAT(SUBSTR("2011-11-11",1,8),"01");
-- 2011-11-01

5 같이 보기

• LAST_DAY
• first_of_this_month