Check if parameter exists?

[Stephen Friedrich]

I have a "baseQuery", i.e. a complex piece of sql, that I have put into an <sql> tag for reuse.
That snippet is used as a subquery in many different queries.
To optimize performance I'd like to add a where clause to the baseQuery itself like so:
        <where>
            <if test="projectId != null">
                t.project_id = ${projectId}
            </if>
            <if test="taskId != null">
                and t.id = ${taskId}
            </if>
        </where>
The problem is that neither "projectId" nor "taskId" parameters are present in all queries.
How can I check if the specific query has these parameters?

[Eduardo Macarron]

Use _parameter.containsKey(xxx)

El día 20 de abril de 2012 17:23, Stephen Friedrich
<stephen....@fortis-it.de> escribió:

[Stephen Friedrich]

Thanks a million! Works perfectly and makes all the difference for my app (10 times speedup for common use cases).

[Mike Fotiou]

Hi Eduardo,

  What is this mysterious "_parameter" value?  Does it represent the parameter map that Mybatis generates when more than one parameter is used in the call to the mapper statement?

Thanks,

Mike

[Eduardo Macarron]

The input parameter is always stored under the key _parameter in the
OGNL context.