The difference between $ and # in MyBatis

Use $ and # in MyBatis to refer to the data passed in,

The difference between the two is:

1. Use # to handle incoming values as strings, and automatically add single quotes to the resulting SQL statement

2. Use $ to directly reference the value passed in (the resulting SQL statement does not enclose a single quotation mark)

3. Using $ easy to cause SQL injection

The problem I encountered:

When using the PostgreSQL database to store data, error:

Error updating database. Cause:org.postgresql.util.PSQLException: Error: The type of the field "message" is JSON, but the type of the expression is character varying
Recommendation: You need to rewrite or convert an expression

The reason for the error is that #{message} is used to reference the message, and the type of the argument becomes a string (the actual type in the database should be JSON)

Use ${message} to resolve

The difference between $ and # in MyBatis