在BIRT中输入参数后更新数据集查询 [英] Updating Data Set query after parameter input in BIRT

问题描述

在BIRT报表设计中传递参数后，如何更改或更新数据集的查询?

How can I change or update a data set's query after a parameter has been passed in BIRT report designing?

详细信息:

我有一个看起来像这样的查询:

I've got a query that looks like this:

WHERE ? 

该参数标记可以保存不同的值，在用户输入参数后，它看起来像这样:

That parameter marker can hold different values, after user input parameter, it would look like this e.g.:

WHERE column_name = 1

或

WHERE column_name = 2

甚至

WHERE column_name IN (1,2)

我为该数据集参数(DSP)创建了一个报告参数(RP)，经过数小时的尝试，我无法更改它.

I created a Report Parameter(RP) for that Data Set Parameter(DSP) and after trying for hours, I couldn't get to change it.

我尝试过:

• 在RP和DSP上创建各种javascript表达式
• 创建一个可更改第一个RP值并返回上一步的RP
• 编辑属性绑定，尽管我无法弄清楚应该如何完成. 为了清楚起见，我正在设计一个报告，而不是将运行时集成到现有应用程序中. 我希望这很清楚，我仍在编辑问题，因此，如果您需要更多信息，请告诉我.

• Creating all sorts of javascript expressions on both, RP and DSP
• Creating a RP that would change the value of the first RP and back to previous step
• Editing the Property Binding, though I couldn't figure it out how exactly it should be done. Just to make it clear, I'm designing a report and not integrating the runtime to an existing application. I hope this is clear enough, I'm still editing the question so if you need more information just let me know.

谢谢

推荐答案

假设您使用的是Oracle DB(其他系统的行为可能有所不同)，则应注意，绑定变量(以JDBC语言:问号)可以仅替换标量值，例如字符串或数字.

Assuming that you are on an Oracle DB (other systems may behave differently) you should be aware that a bind variable (in JDBC speech: the question mark) can replace a scalar value only, e.g. a string or a number.

但是您希望输入类似 list 的数字. 因此，在这种情况下，绑定变量将无济于事.

But you want something like a list of numbers as input. Thus a bind variable won't help you in this case.

可能最简单的方法来实现您想要的是:

Probably the easiest way to achieve what you want is this:

在查询中，输入:

WHERE column_name in (1) -- $REPLACE_THIS$

请注意，我在查询中使用注释作为标记. 然后，在查询的beforeOpen事件中，如下修改查询文本:

Note that I am using a comment in the query as a marker. Then, in the query's beforeOpen event, modify the query text like this:

// construct a comma-separated string representation of your list
// based on your report parameter (exercise left to the reader)
// var replacement = my_to_sql_csv(params["my_report_parameter"].value);

// for demonstration use:
var replacement = "1,2";

// modify the `IN` expression inside the SQL
this.queryText = this.queryText.replaceAll("(1) -- $REPLACE_THIS$", "(" + replacement + ")";

就是这样.

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