How to escape dynamically generated String values in a JCR SQL2 query?

Question

Let's pretend I have a JCR 2 query string that is made like this:

String sql2Query = "SELECT * FROM [cq:PageContent] " +
                   "WHERE [aProperty] <> \" + aValue + "\"";

Are there helper methods using which I can escape aValue?

By the way, I already know that in SQL2 we can use placeholders for queries and let the framework take care of escaping of values for us, but if I were to create this query dynamically, how can I escape aValue to prevent SQL injection as well as construction of broken queries?

Thomas Mueller Thomas Mueller · Accepted Answer · 2014-12-02T12:30:25

Yes, you can use placeholders. Even dynamically created queries can use placeholders.

As for SQL-2, you need to use single quotes, not double quotes. Example:

SELECT * FROM [cq:PageContent]
WHERE [aProperty] <> 'Joe''s Taxi'

You only need to escape single quotes, using a single quote escape character:

String aValue = "Joe's Taxi";
String sql2Query = "SELECT * FROM [cq:PageContent] " +
    "WHERE [aProperty] <> '" + aValue.replaceAll("'", "''") + "'";

If you want to use XPath, you can use single quotes or double quotes, but usually single quotes are used as well (the same as in SQL-2). XPath queries don't support placeholders currently.

How to escape dynamically generated String values in a JCR SQL2 query?

2 Answers