SQL Cheat Sheet: Dates & Times (SQL Server / T-SQL)

Dates are where SQL queries quietly go wrong.

Ages come out a year too old, weeks start on the wrong day, and empty days vanish from your reports.

This 2-page cheat sheet gives you ready-to-use T-SQL for the date jobs that come up again and again.

What’s inside

• Exact age in years, including why DATEDIFF alone gets birthdays wrong
• Quarter, ISO week number and day of the year
• Start and end of this quarter and last quarter, on any version of SQL Server
• Round dates down to the week, month, quarter or year with DATETRUNC
• Find this Monday, next Monday and this Friday, whatever your DATEFIRST setting
• Weekday or weekend, and counting working days between two dates
• Turn seconds into hh:mm:ss
• The date formats you’ll actually use, with their CONVERT style numbers
• Read UK and US dates correctly with TRY_PARSE
• Build dates and times from separate parts
• Convert UTC to UK time, with BST handled for you
• Build a calendar of dates, and show days with no sales as 0
• A quick guide to date part names and the short forms that catch people out

Who it’s for

• Analysts and developers working with dates in SQL Server
• Anyone building reports by day, week, month or quarter
• Office workers moving from Excel to SQL

Format

A 2-page A4 PDF, ready to print or keep open on a second screen.

Every example uses one fixed date, with the expected result shown beside the query.

For personal use only.

From Rosleecia Productions.