How to get substring in SQLIte?

Use the substr function.

From the list of core functions:

substr(X,Y,Z) substr(X,Y) substring(X,Y,Z) substring(X,Y)

The substr(X,Y,Z) function returns a substring of input string X that begins with the Y-th character and which is Z characters long. If Z is omitted then substr(X,Y) returns all characters through the end of the string X beginning with the Y-th. The left-most character of X is number 1. If Y is negative then the first character of the substring is found by counting from the right rather than the left. If Z is negative then the abs(Z) characters preceding the Y-th character are returned. If X is a string then characters indices refer to actual UTF-8 characters. If X is a BLOB then the indices refer to bytes.

substring() is an alias for substr() beginning with SQLite version 3.34.

To get the substring in SQLite

You can use the builtin function in SQLite which is substr(X,Y,Z). The x field represents the string input to be sliced, the y field represents the starting point using an index, and the z field represents the substring length.

===============================
|Database Table : **articles**|
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|id | description             |
-------------------------------
|29 | Lorem ipsum domit       |
===============================

Now we will try to make a select query for our description

SELECT substr(description,1,4) FROM articles where id='29';

Output would be: Lore instead of Lorem ipsum domit

To extend existing answers, starting from SQLite 3.34.0:

The substr() SQL function can now also be called "substring()" for compatibility with SQL Server.

substring(X,Y) "substring()" is an alias for "substr()" beginning with SQLite version 3.34.