1.46. Common functions of SQLite

发布时间 :2025-10-25 12:31:10 UTC      

SQLite has many built-in functions for dealing with string or numeric data. Here are some useful SQLite built-in functions, all of which are case-insensitive, which means you can use these functions in lowercase or uppercase or mixed form. For more information, please check the official documentation of SQLite:

Serial number

Function & description

1

SQLite COUNT function

SQLite COUNT The aggregate function is used to calculate the number of rows in a database table.

2

SQLite MAX function

SQLite MAX The aggregate function allows us to select the maximum value of a column.

3

SQLite MIN function

SQLite MIN The aggregate function allows us to select the minimum value of a column.

4

SQLite AVG function

SQLite AVG The aggregate function calculates the average of a column.

5

SQLite SUM function

SQLite SUM Aggregate functions allow you to calculate the sum for a numeric column.

6

SQLite RANDOM function

SQLite RANDOM Function returns a pseudo-random integer between-9223372036854775808 and + 9223372036854775807.

7

SQLite ABS function

SQLite ABS Function returns the absolute value of a numeric parameter.

8

SQLite UPPER function

SQLite UPPER Function to convert a string to uppercase letters.

9

SQLite LOWER function

SQLite LOWER Function to convert a string to lowercase letters.

10

SQLite LENGTH function

SQLite LENGTH Function returns the length of the string.

11

SQLite sqlite_version function

SQLite sqlite_version Function returns the version of the SQLite library.

Before we begin to explain these function examples, assume that the COMPANY table has the following records:

ID          NAME        AGE         ADDRESS     SALARY
----------  ----------  ----------  ----------  ----------
1           Paul        32          California  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

1.46.1. SQLite COUNT function

SQLite COUNT The aggregate function is used to calculate the number of rows in a database table. Here is an example:

sqlite> SELECT count(*) FROM COMPANY;

Above. SQLite SQL Statement will produce the following results:

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

1.46.2. SQLite MAX function

SQLite MAX The aggregate function allows us to select the maximum value of a column. Here is an example:

sqlite> SELECT max(salary) FROM COMPANY;

Above. SQLite SQL Statement will produce the following results:

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

1.46.3. SQLite MIN function

The SQLite MIN aggregate function allows us to select the minimum value of a column. Here is an example:

sqlite> SELECT min(salary) FROM COMPANY;

The above SQLite SQL statement produces the following results:

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

1.46.4. SQLite AVG function

The SQLite AVG aggregate function calculates the average of a column. Here is an example:

sqlite> SELECT avg(salary) FROM COMPANY;

The above SQLite SQL statement produces the following results:

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

1.46.5. SQLite SUM function

The SQLite SUM aggregate function allows you to calculate the sum for a numeric column. Here is an example:

sqlite> SELECT sum(salary) FROM COMPANY;

The above SQLite SQL statement produces the following results:

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

1.46.6. SQLite RANDOM function

The SQLite RANDOM function returns a pseudo-random integer between-9223372036854775808 and + 9223372036854775807. Here is an example:

sqlite> SELECT random() AS Random;

The above SQLite SQL statement produces the following results:

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

1.46.7. SQLite ABS function

The SQLite ABS function returns the absolute value of a numeric parameter. Here is an example:

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

The above SQLite SQL statement produces the following results:

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

1.46.8. SQLite UPPER function

The SQLite UPPER function converts a string to uppercase letters. Here is an example:

sqlite> SELECT upper(name) FROM COMPANY;

The above SQLite SQL statement produces the following results:

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

1.46.9. SQLite LOWER function

The SQLite LOWER function converts a string to lowercase letters. Here is an example:

sqlite> SELECT lower(name) FROM COMPANY;

The above SQLite SQL statement produces the following results:

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

1.46.10. SQLite LENGTH function

The SQLite LENGTH function returns the length of the string. Here is an example:

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

The above SQLite SQL statement produces the following results:

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

1.46.11. SQLite sqlite_version function

The SQLite sqlite_version function returns the version of the SQLite library. Here is an example:

sqlite> SELECT sqlite_version() AS 'SQLite Version';

The above SQLite SQL statement produces the following results:

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

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