Dates & Time on Andy M Mallon - AM²

Consuming SQL Agent dates & durations

Fri, 07 Mar 2025 16:17:43 -0500

SQL Agent’s schema is older than me. It handles dates, times, and durations like it’s 1980 by using integers instead of date/time data types. My buddy Aaron Bertrand talks more about Dating Responsibly so that you can have a good datetime with your own database.

Not all stats should be auto-updated

Thu, 29 Aug 2024 11:19:07 -0400

Statistics auto-updates are generally a good thing–auto-update of statistics is the default behavior in SQL Server. Having the freshest information about the data “shape” helps to inform the best selection of an execution plan for queries.

Except for when it doesn’t.

Because It Depends™️

Let’s talk about the trade-offs.

Why are there no "Daylight Time" time zones in SQL Server?

Thu, 21 Oct 2021 23:11:06 -0400

Question

I am converting the times of some datetimeoffset columns from UTC to Eastern. I am doing this via the command

UPDATE MyTable SET MyColumn = MyColumn AT TIME ZONE 'Eastern Standard Time'

This seemed to be working correctly (times were shifted 4 hours earlier and now have a -04:00 offset, exactly what I wanted), but then I realized that it's not EST, it's EDT right now.

Question Regarding ISDATE Function and DATENAME Functions

Thu, 01 Jul 2021 23:50:20 -0400

Question

We have had an issue this morning with a report failing due to the following error:

"Conversion failed when converting date and/or time from character string"

The issue is that in the database we had a value (in a VARCHAR field) of: '31.07/2021'

SQL Server 2012 equivalent of AT TIME ZONE capability

Wed, 30 Jun 2021 22:11:31 -0400

Question

Is there a way in SQL Server 2012 to get what the server time zone would be on a particular date/time? In SQL Server 2016, you have AT TIME ZONE, but that's not available in 2012. I have a datetimeoffset and I need to convert it to the server's timezone (on that date) before truncating it to datetime. SWITCHOFFSET only works if you know the offset, but for servers that change their timezone twice yearly, the offset will flip back and forth.

Job management: How to get the next running date by querying MSDB

Fri, 27 Nov 2020 10:10:17 -0500

Question

Table sysjobschedules contains 2 columns next_run_date and next_run_time. With the help of sysschedules and column enable it should be easy to determine the next running date/time of a specific job.

However, when you change a schedule, sysjobschedules is only refreshed 20 minutes after alteration by the Sql Server Agent.

Replication of only updates and inserts

Wed, 14 Oct 2020 16:01:08 -0400

Question

I have two sql servers, in the first I want to keep the data from the last three months and in the second I want to keep all the data with the purpose of getting historical reports. I know how to do a transactional replica but I don't know how to replicate only the inserts and updates, I don't want to replicate the deletions.

sp_update_schedule says @schedule_id does not exist

Tue, 06 Oct 2020 12:53:39 -0400

Question

I wrote a script that reads job schedules from msdb.dbo.sysschedules and runs sp_update_schedule to change the active_start_time for a given subset of jobs. In each case, sp_update_schedule fails with the message "The specified @schedule_id('xxx') does not exist". (MessageID 14262, Severity 16)

How to create date buckets in T-SQL

Mon, 28 Oct 2019 10:00:47 -0400

I was fiddling around with some data, looking at making a quick aging report. I probably should have reached for Power BI Desktop, but sometimes I can be stubborn, and I wanted to get my T-SQL to work–if nothing else to figure out how to make it work.

convert sql-excel date to recognizable format

Sat, 26 Oct 2019 10:27:37 -0400

Question

I have a large csv file(1.1G) exported from SQL Server. I would like to do data wrangling in python, but I had a few problems doing this. The original csv file dates look like this 00:07.5, 00:08.3, 00:48.7, I can manually convert them to 1/12/2015 12:00:07 am, 1/12/2015 12:00:08 am, 1/12/2015 12:00:49 am in excel by formatting the entire column to make it in d/m/yy h:mm:ss, but sometimes output is weird like 100:00:00, or it just kept the time but not the dates, when I finally successfully did this, I noticed that the file size had shrank to 36.6 MB from 1.1G. I received the excel notification:

Updates to the Data Blogger Resource Kit

Wed, 09 Oct 2019 10:31:46 -0400

Earlier this year, I published the first crack at a Data Blogger Resource Kit. When I initially created the kit, I wasn’t quite sure exactly what direction I would go with it. In the months since, I’ve started to get a better idea of where I want to go, and I’ve collected some additional resources that might be helpful for folks who are bloggers or who are interested in becoming bloggers.

Code to purge data based on creation date

Thu, 04 Apr 2019 08:30:16 -0400

Only one thing can spark more joy than cleaning up old data. Doggos. Yesterday, I talked about batching deletes, and the day before I talked about how much I like to delete data, and why it's necessary to do it, despite being a data packrat.

Today, let’s look at just one scenario, and how I like to handle it. In my experience, this is one of the most common purge requirements (and probably the easiest), so first, let’s look at the business requirements.

Updated shortcuts cheat sheet -- Now with Azure Data Studio

Thu, 08 Feb 2018 21:05:46 -0500

Updated (2018-09-24): SQL Ops Studio is now generally available, and has been renamed Azure Data Studio. I've updated the cheat sheet to reflect the name change, but the shortcuts remain the same. Feel free to grab the updated PDF with the new label, or keep the old one to prove your OG status.

Nearly two year ago, I first published my Shortcuts cheat sheet. Since then, thousands of people have downloaded it. I’ll be the first to admit that I didn’t expect it to be as much of a hit as it has been. When I give my one-hour talk in person, I bring card stock handouts of my cheat sheets, too. I also ask people for their favorite shortcuts, and I’ve learned some great new hidden gems.

Converting date stored as a varchar

Thu, 06 Apr 2017 10:00:51 -0400

Question

I'm creating a query that has a column of dates stored as a VARCHAR in the format DD-MMM-YYYY.

Could you tell me how I can convert this into date format please?

I don't want to alter the original table in any way, as it's not mine to tinker!

How often to update SQL Server?

Mon, 02 Jan 2017 19:10:39 -0500

Question

I am a new DBA at a company that has never had a DBA before me. SQL Servers are never upgraded unless it is part of a Windows Update on the server. Service Packs (or CUs) are never installed. We have a mix of versions from 2000 to 2014.

I have 3 tables with dates to which I want to join to a date dimension table but it is returning many duplicates with left joins

Tue, 16 Aug 2016 11:55:03 -0400

Question

I have 4 tables with dates to which I want to join to a date dimension table but it is returning many duplicates with left joins.

Tables are basically a date field which I want to count.

 mdate datetime, mordate varchar(10),fteam varchar(20)
 sdate datetime,fteam varchar(20)
 bdate datetime,fteam varchar(20)

These are actually one table with the separate dates which I am joining 3 times to the dimension table to get one dataset. Also this table

Using DateTime Variable In Where Clause

Wed, 30 Mar 2016 15:22:09 -0400

Question

I am trying to pull all data where a sale date is >= to a certain datetime. When I execute my query I get an error of:

Msg 241, Level 16, State 1, Line 15
Conversion failed when converting date and/or time from character string.

sp_autostats: object-level auto update statistics

Tue, 15 Dec 2015 11:00:00 -0500

In SQL Server, auto-update statistics is a database level setting. It’s right there:

I’m not going to say whether I think Auto Update Statistics should be on or off. Instead, I’m going to argue that there are definitely scenarios when you want to have this on AND there are scenarios where you want it turned off. Can you really have this both ways? Absolutely.