If you need to calculate the number of seconds that have passed since a given date and time, you can use the UNIXEPOCH() function.
Note that this function was introduced in SQLite 3.38.0, so it will only work if you’re using SQLite 3.38.0 or later.
Continue readingIn PostgreSQL, we can use the initcap() function to format a string of text to use initial capitals. That is, it converts the first letter of each word to upper case and the rest to lower case.
Here are a couple of ways to show a list of databases when using psql with PostgreSQL.
The first option can be used when we’re already connected to PostgreSQL. The second option can be used when we don’t currently have a connection to Postgres.
Continue readingIn SQLite, we can use the DATE() function to add a given number of days to a date.
If we’re dealing with datetime values, we can use the DATETIME() function.
When using the SQLite command line interface (CLI), by default, whenever a query returns a null value, the output is the empty string ('').
We can change this by using the -nullvalue command line option when launching SQLite.
We can also use the .nullvalue dot command if we’re already in the SQLite CLI.
In MariaDB, we can use the UPPER() function to convert lowercase characters to their uppercase equivalent.
We can alternatively use UCASE(), which is a synonym of UPPER().
Below is a full list of JSON functions and JSON operators available in SQLite.
Continue readingWhen working with MariaDB, you may occasionally find yourself needing to return all rows that contain at least one numerical digit.
In such cases, you may find the following example useful.
Continue readingIn SQLite we can use the upper() function to convert lowercase characters to uppercase.
Here are two methods for returning the Julian Day in SQLite.
The Julian Day is the fractional number of days since noon in Greenwich on November 24, 4714 B.C. It’s the continuous count of days since the beginning of the Julian period, and is used primarily by astronomers, and in software for easily calculating elapsed days between two events.
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