The + operator allows us to add one or more days to a given date in PostgreSQL. We have a few options when it comes to specifying the actual number of days.
Category: PostgreSQL
Subtract Days from a Date in PostgreSQL
We can subtract one or more days from a date in PostgreSQL with the - operator.
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 -.
PostgreSQL VALUES Command Explained
In PostgreSQL, the VALUES command returns a set of one or more rows as a table. It’s a table value constructor that can be used as part of a larger command, or as a standalone SQL statement.
5 Ways to Select Rows with the Minimum Value for their Group in SQL
Here are five options for using SQL to return only those rows that have the minimum value within their group.
These examples work in most major RDBMSs, including MySQL, MariaDB, Oracle, PostgreSQL, SQLite, and SQL Server.
Continue reading3 Ways to Select the Row with the Minimum Value in SQL
Here are three examples of using SQL to find and select the row with the minimum value in a given column.
The examples work in most major RDBMSs, including MySQL, MariaDB, PostgreSQL, SQLite, Oracle, and SQL Server.
Continue readingFix “ERROR: missing FROM-clause entry for table” in PostgreSQL when using UNION, EXCEPT, or INTERSECT
If you’re getting “ERROR: missing FROM-clause entry for table” in PostgreSQL when using an operator such as UNION, INTERSECT, or EXCEPT, it could be because you’re qualifying a column name with its table name.
To fix this, either remove the table name or use a column alias.
Continue readingFix “ERROR: each UNION query must have the same number of columns” in PostgreSQL
When using the UNION operator in PostgreSQL, if you encounter an error that reads “ERROR: each UNION query must have the same number of columns“, it’s because there’s a mismatch in the number of columns returned by the queries on either side of the UNION operator.
This error occurs when the number of columns returned by each SELECT statement is different.
The way to fix this is to ensure that both SELECT statements return the same number of columns.
How UNION Works in PostgreSQL
In PostgreSQL, the UNION operator combines the results from multiple queries into a single result set.
How INTERSECT Works in PostgreSQL
In PostgreSQL, the INTERSECT operator combines two queries, but returns only those rows that are returned in both queries.