PostgreSQL DATEADD() Equivalent

Updated 20 April 2024 to include the date_add() function.

SQL Server has its DATEADD() function that adds an interval to a date value. MySQL’s DATE_ADD() and ADDDATE() for does the same thing, as does MariaDB’s DATE_ADD() and ADDDATE(). SQLite has a DATE() function that also provides the option of adding an interval to a given date.

Prior to version 16, PostgreSQL didn’t have a DATEADD() or equivalent function. But with PostgreSQL 16 came with the introduction of the date_add() function, which allows us to add an interval to a timestamp with time zone.

We can also add and subtract values from dates with date/time operators such as + and -.

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SQL Server SHOW TABLES Equivalent

Every now and then I find myself typing SHOW TABLES in SQL Server, expecting to get a list of tables.

That would make perfect sense if I was using MySQL or MariaDB. But SQL Server/T-SQL doesn’t have a SHOW TABLES statement like MySQL or MariaDB, so it never works. And I keep forgetting. But fortunately, SQL Server does have alternatives.

Here are five options for getting a list of tables in SQL Server. These can be used whenever you’re trying to find that elusive SHOW TABLES statement in SQL Server.

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SQLite INTERSECT Operator

In SQLite, the INTERSECT operator is used to create a compound SELECT statement that returns the intersection of the results of the left and right SELECT statements. In other words, it combines two queries, but returns only those rows that are returned in both queries.

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Find All Non-Numeric Values in a Column in Oracle

If you ever encounter a character column that should be a numeric column, there’s always a possibility that it contains non-numeric data that you don’t know about.

In Oracle Database, you can run a query like the following to return non-numeric data from the column.

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