You can use the sys.triggers catalog view to return a list of triggers in a database in SQL Server.
This view contains a row for each object that is a trigger, with a type of TR or TA.
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Database Management Systems
Examples of Formatting ‘datetimeoffset’ in SQL Server using Standard Format Strings (T-SQL)
I thought it would be interesting to run a few quick queries to see how various formatting strings affect the formatting of date/time values.
Create a “Last Modified” Column in SQL Server
Some database tables include a “last modified” column, which stores the date and time that the row was last updated. Each time the row is updated, the date is updated to reflect the date and time of that update.
In SQL Server, you can use a trigger to perform this update.
A trigger is a special type of stored procedure that automatically runs when an event occurs in the database server.
You can use the CREATE TRIGGER statement to create a trigger when using T-SQL. This statement can be used to create a DML, DDL, or logon trigger.
PostgreSQL Date & Time Functions
Below is a full list of date/time functions available in PostgreSQL.
Continue readingPostgreSQL Math Functions
Below is a full list of mathematical functions available in PostgreSQL.
These are arranged into the following four categories:
- Mathematical Functions
- Random Functions
- Trigonometric Functions
- Hyperbolic Functions
“Cannot drop the trigger” Error when Trying to Drop a Logon Trigger? Try This.
Are you’re trying to drop a logon trigger in SQL Server, but you’re getting an error like the following?
“Cannot drop the trigger ‘trigger_name’, because it does not exist or you do not have permission.”
It could be because you’re missing the ON ALL SERVER argument.
SQL Server IF vs IIF(): What’s the Difference?
Students learning a new programming language will often start their first lesson with an IF statement, where their statement will return a value only if the expression is true.
They might then progress to an IF... ELSE statement, where they can determine another value to return if the expression is false. So therefore, return one value if the expression is true, and another value if it’s false.
SQL Server certainly includes the IF... ELSE statement in its T-SQL toolbox.
SQL Server also includes the IIF() function, which does a similar thing, but with a more concise syntax.
But there are some subtle differences.
Continue readingHow to Test for Overlapping Dates in PostgreSQL
In PostgreSQL, you can use the OVERLAPS operator to test for overlapping time periods.
The function returns true when two time periods (defined by their endpoints) overlap, and false when they do not overlap.
Continue readingHow to Format Numbers as Currency in PostgreSQL
To format a number as currency in Postgres, you can either convert it to the money data type, or use to_char() to convert it to text that includes the appropriate currency symbol.
This obviously assumes that the number isn’t already stored using the money type.
Below are examples of each of these options.
Continue readingHow to Pause the Execution of a Statement in PostgreSQL
PostgreSQL includes three functions that allow you to delay the execution of the server process. the execution of a statement.
In other words, you can run a statement and have it pause half way through, before continuing on its merry way.
The three functions are:
These are all very similar, but they work in slightly different ways.
Below are examples of each one.
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