Why Does SQLite String Concatenation Using ' ' Return '0'?

Understanding String Concatenation in SQLite

In database queries, concatenating strings often arises, and in SQLite, this operation differs from other programming languages.

Problem Statement:

When executing an SQL query involving string concatenation using the ' ' operator, unexpected '0' results are returned.

Query in Question:

select  locationname + '<p>' from location;</p>

Incorrect Result:

A list of 0s instead of the expected string with concatenated location names and '

' literals.

Correct Approach:

In SQLite, string concatenation is performed using the '||' operator, unlike the ' ' operator used in other programming languages.

Corrected Query:

select  locationname || '<p>' from location;</p>

SQLite Documentation Explanation:

The SQLite documentation states that the '||' operator is explicitly used for string concatenation, joining together the two operand strings.

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