SQLite - Useful Functions

SQLite has many built-in functions to perform processing on string or numeric data. Following is the pst of few useful SQLite built-in functions and all are case in-sensitive which means you can use these functions either in lower-case form or in upper-case or in mixed form. For more details, you can check official documentation for SQLite.

Before we start giving examples on the above-mentioned functions, consider COMPANY table with the following records.

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
1           Paul        32          Capfornia  20000.0
2           Allen       25          Texas       15000.0
3           Teddy       23          Norway      20000.0
4           Mark        25          Rich-Mond   65000.0
5           David       27          Texas       85000.0
6           Kim         22          South-Hall  45000.0
7           James       24          Houston     10000.0

SQLite COUNT Function

SQLite COUNT aggregate function is used to count the number of rows in a database table. Following is an example −

sqpte> SELECT count(*) FROM COMPANY;

The above SQLite SQL statement will produce the following.

count(*)
----------
7

SQLite MAX Function

SQLite MAX aggregate function allows us to select the highest (maximum) value for a certain column. Following is an example −

sqpte> SELECT max(salary) FROM COMPANY;

The above SQLite SQL statement will produce the following.

max(salary)
-----------
85000.0

SQLite MIN Function

SQLite MIN aggregate function allows us to select the lowest (minimum) value for a certain column. Following is an example −

sqpte> SELECT min(salary) FROM COMPANY;

The above SQLite SQL statement will produce the following.

min(salary)
-----------
10000.0

SQLite AVG Function

SQLite AVG aggregate function selects the average value for a certain table column. Following is an the example −

sqpte> SELECT avg(salary) FROM COMPANY;

The above SQLite SQL statement will produce the following.

avg(salary)
----------------
37142.8571428572

SQLite SUM Function

SQLite SUM aggregate function allows selecting the total for a numeric column. Following is an example −

sqpte> SELECT sum(salary) FROM COMPANY;

The above SQLite SQL statement will produce the following.

sum(salary)
-----------
260000.0

SQLite RANDOM Function

SQLite RANDOM function returns a pseudo-random integer between -9223372036854775808 and +9223372036854775807. Following is an example −

sqpte> SELECT random() AS Random;

The above SQLite SQL statement will produce the following.

Random
-------------------
5876796417670984050

SQLite ABS Function

SQLite ABS function returns the absolute value of the numeric argument. Following is an example −

sqpte> SELECT abs(5), abs(-15), abs(NULL), abs(0), abs("ABC");

The above SQLite SQL statement will produce the following.

abs(5)      abs(-15)    abs(NULL)   abs(0)      abs("ABC")
----------  ----------  ----------  ----------  ----------
5           15                      0           0.0

SQLite UPPER Function

SQLite UPPER function converts a string into upper-case letters. Following is an example −

sqpte> SELECT upper(name) FROM COMPANY;

The above SQLite SQL statement will produce the following.

upper(name)
-----------
PAUL
ALLEN
TEDDY
MARK
DAVID
KIM
JAMES

SQLite LOWER Function

SQLite LOWER function converts a string into lower-case letters. Following is an example −

sqpte> SELECT lower(name) FROM COMPANY;

The above SQLite SQL statement will produce the following.

lower(name)
-----------
paul
allen
teddy
mark
david
kim
james

SQLite LENGTH Function

SQLite LENGTH function returns the length of a string. Following is an example −

sqpte> SELECT name, length(name) FROM COMPANY;

The above SQLite SQL statement will produce the following.

NAME        length(name)
----------  ------------
Paul        4
Allen       5
Teddy       5
Mark        4
David       5
Kim         3
James       5

SQLite sqpte_version Function

SQLite sqpte_version function returns the version of the SQLite pbrary. Following is an example −

sqpte> SELECT sqpte_version() AS  SQLite Version ;

The above SQLite SQL statement will produce the following.

SQLite Version
--------------
3.6.20