SQLite Expressions

SQLite Expressions are the combination of one or more values, operators and SQL functions. These expressions are used to evaluate a value.

SQLite expressions are written in query language and used with SELECT statement.

Syntax:

SELECT column1, column2, columnN   

FROM table_name   

WHERE [CONDITION | EXPRESSION]; 

There are mainly three types of SQLite expressions:

1) SQLite Boolean Expression

SQLite Boolean expressions are used to fetch the data on the basis of matching single value.

Syntax:

SELECT column1, column2, columnN   

FROM table_name   

WHERE SINGLE VALUE MATCHTING EXPRESSION;  

Example:

We have an existing table named “STUDENT”, having the following data:

See this simple example of SQLite Boolean expression.

SELECT * FROM STUDENT WHERE FEES = 20000;   

Output:

2) SQLite Numeric Expressions

SQLite Numeric expression is used to perform any mathematical operations in the query.

Syntax:

SELECT numerical_expression as  OPERATION_NAME  

[FROM table_name WHERE CONDITION] ;   

Example1:

SELECT (25 + 15) AS ADDITION;

Output:

Numeric expressions contain several built-in functions like avg(), sum(), count(), etc. These functions are known as aggregate data calculation functions.

SELECT COUNT(*) AS “RECORDS” FROM STUDENT;

Output:

3) SQlite Date Expression

SQlite Date expressions are used to fetch the current system date and time values.

Syntax:

SELECT CURRENT_TIMESTAMP;   

SELECT CURRENT_TIMESTAMP;

Output: