If you need to add a “count” column to the result set of a database query when using SQLite, you can use the count() function to provide the count, and the GROUP BY clause to specify the column for which to group the results.
Category: SQLite
How SQLite Count() Works
The SQLite count() function can be used to return the number of rows in a result set.
It can also be used to return the number of times a given column is not NULL in the result set.
It can be used in two ways. If you pass in the asterisk (*) wildcard character, it will return the total number of rows in the group. If you provide the name of a column, it will return the number of times that column is not NULL.
SQLite Date & Time Functions
SQLite supports five functions for working with dates and times. These are:
All of these functions accept a time string as an argument. They also accept other arguments for modifying/formatting the output.
The strftime() function is the most versatile function of the five. In fact, this function can do everything the other four can.
In other words, you could use strftime() for all your date and time formatting requirements. The other four functions are available solely for convenience.
How the Strftime() Function Works in SQLite
The SQLite strftime() function enables you to return a date and time value in a specified format.
The actual date/time value returned is based on a time string that you provide as an argument when you call the function, as well as any modifiers you include (as optional arguments). A modifier allows you to change the date, such as add a number of days, set it to local time, etc
Continue readingHow the JulianDay() Function Works in SQLite
The SQLite julianday() function returns the number of days since noon in Greenwich on November 24, 4714 B.C. (using the Proleptic Gregorian calendar).
If using the proleptic Julian calendar, this is Monday, January 1, 4713 BC.
Julian day is the continuous count of days since the beginning of the Julian Period. It’s typically used by astronomers, software, etc to calculate elapsed days between two events.
To use this function, you need to provide a time string, plus any (optional) modifiers. A modifier allows you to change the date, such as add a number of days, set it to local time, etc
Continue readingHow the DateTime() Function Works in SQLite
The SQLite datetime() function enables you to return a date and time value based on a time string and any modifiers.
It returns the date in this format: YYYY-MM-DD HH:MM:SS
To use this function, you need to provide a time string, plus any (optional) modifiers. A modifier allows you to change the date, such as add a number of days, set it to local time, etc
Continue readingHow the Time() Function Works in SQLite
SQLite has a time() function that enables you to return a time value based on a time string and any modifiers.
It returns the time in this format: HH:MM:SS
To use this function, you need to provide a time string, plus any (optional) modifiers. A modifier allows you to change the time, such as add a number of hours, set it to local time, etc
Continue readingHow the Date() Function Works in SQLite
SQLite has a date() function that enables you to return a date value based on a time string and any modifiers.
It returns the date in this format: YYYY-MM-DD
To use this function, you need to provide a time string, plus any (optional) modifiers. A modifier allows you to change the date, such as add a number of days, set it to local time, etc
Continue readingValid Format String Substitutions for the SQLite Strftime() Function
The table below contains the valid format string substitutions that you can use with the strftime() function in SQLite.
Valid Time String Formats for SQLite Date/Time Functions
Below is a list of valid time string formats that you can use in any date and time function in SQLite.
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