Monday, 18 August 2014

undefined undefined

Date / Time related queries

Get the first day of the month
Quickly returns the first day of current month. Instead of current month you want to find first day of month where a date falls, replace SYSDATE with any date column/value.

SELECT TRUNC (SYSDATE, 'MONTH') "First day of current month"
FROM DUAL;



Get the last day of the month
This query is similar to above but returns last day of current month. One thing worth noting is that it automatically takes care of leap year. So if you have 29 days in Feb, it will return 29/2. Also similar to above query replace SYSDATE with any other date column/value to find last day of that particular month.

SELECT TRUNC (LAST_DAY (SYSDATE)) "Last day of current month"
FROM DUAL;



Get the first day of the Year
First day of year is always 1-Jan. This query can be use in stored procedure where you quickly want first day of year for some calculation.

SELECT TRUNC (SYSDATE, 'YEAR') "Year First Day" FROM DUAL;


Get the last day of the year
Similar to above query. Instead of first day this query returns last day of current year.

SELECT ADD_MONTHS (TRUNC (SYSDATE, 'YEAR'), 12) - 1 "Year Last Day" FROM DUAL


Get number of days in current month
Now this is useful. This query returns number of days in current month. You can change SYSDATE with any date/value to know number of days in that month.

SELECT CAST (TO_CHAR (LAST_DAY (SYSDATE), 'dd') AS INT) number_of_days
FROM DUAL;



Get number of days left in current month
Below query calculates number of days left in current month.

SELECT SYSDATE,
LAST_DAY (SYSDATE) "Last",
LAST_DAY (SYSDATE) - SYSDATE "Days left"
FROM DUAL;



Get number of days between two dates
Use this query to get difference between two dates in number of days.

SELECT ROUND ( (MONTHS_BETWEEN ('01-Feb-2014', '01-Mar-2012') * 30), 0)
num_of_days
FROM DUAL;


OR

SELECT TRUNC(sysdate) - TRUNC(e.hire_date) FROM employees;
Use second query if you need to find number of days since some specific date. In this example number of days since any employee is hired.

Display each months start and end date upto last month of the year
This clever query displays start date and end date of each month in current year. You might want to use this for certain types of calculations.

SELECT ADD_MONTHS (TRUNC (SYSDATE, 'MONTH'), i) start_date,
TRUNC (LAST_DAY (ADD_MONTHS (SYSDATE, i))) end_date
FROM XMLTABLE (
'for $i in 0 to xs:int(D) return $i'
PASSING XMLELEMENT (
d,
FLOOR (
MONTHS_BETWEEN (
ADD_MONTHS (TRUNC (SYSDATE, 'YEAR') - 1, 12),
SYSDATE)))
COLUMNS i INTEGER PATH '.');



Get number of seconds passed since today (since 00:00 hr)

SELECT (SYSDATE - TRUNC (SYSDATE)) * 24 * 60 * 60 num_of_sec_since_morning
FROM DUAL;



Get number of seconds left today (till 23:59:59 hr)

SELECT (TRUNC (SYSDATE+1) - SYSDATE) * 24 * 60 * 60 num_of_sec_left
FROM DUAL;


Related Posts:

  • Database administration queries Database administration queries Database version informationReturns the Oracle database version. SELECT * FROM v$version; Database default information Some system default information. SELECT username,profile,default_ta… Read More
  • Normalization In SQL Normalization In SQL,MY SQL and Oracle What is normalization ? Defination : Normalization is the process of efficiently organizing data in a database. There are two goals of the normalization process:  1. eliminat… Read More
  • Oracle date and time function related queries Date / Time related queries Get the first day of the month Quickly returns the first day of current month. Instead of current month you want to find first day of month where a date falls, replace SYSDATE with any date colu… Read More
  • Most Important Data dictionary Queries.. Data dictionary queries Check if a table exists in the current database schema A simple query that can be used to check if a table exists before you create it. This way you can make your create table script rerunnable. Just… Read More
  • SQL Functions(ddl,dml,dcl & tcl) with Examples There are 4 types of sql functions 1.DML 2.DDL 3.DCL 4.TCL Now lets see one by one 1.DML DML is abbreviation of Data Manipulation Language. It is used to retrieve, store, modify, delete, insert and update data in databa… Read More

0 comments:

Post a Comment

Copyright © 2025 ORACLE-FORU - SQL, PL/SQL and ORACLE D2K(FORMS AND REPORTS) collections | Powered by Blogger
Design by N.Design Studio | Blogger Theme by NewBloggerThemes.com