可选where子句jasper报告

Question

SELECT name, phone_office, billing_address_city, billing_address_street, billing_address_country 
FROM accounts
WHERE ($P!{EmployeeID} is null or assigned_user_id = $P!{EmployeeID})
ORDER BY billing_address_country, billing_address_city

.../flow.html?_flowId=viewReportFlow&reportUnit=/reports/samples/EmployeeAccounts&EmployeeID=sarah_id

但是当我移除EmployeeID参数时，我希望移除过滤器。所以所有的结果都应该显示出来。

.../flow.html?_flowId=viewReportFlow&reportUnit=/reports/samples/EmployeeAccounts

我的问题是，在sql查询中传递可选where的正确方式是什么。

Answer 1

好的，让我们看看样品。

例如，我们有一个查询：

SELECT id, city, street FROM address WHERE city=$P{inputParamCity} ORDER BY city

但是我们的输入ParamCity可以是不确定的。在本例中，我们得到了一个错误：

Error filling print... Error preparing statement for executing the report query : 
SELECT id, city, street FROM address WHERE city=? ORDER BY city

<parameter name="whereClause" class="java.lang.String" isForPrompting="false">
    <defaultValueExpression><![CDATA[()$P{inputParamCity} == null || $P{inputParamCity}.isEmpty()) ? "1=1" : "city='" + $P{inputParamCity} + "'"]]></defaultValueExpression>
</parameter>

<queryString>
    <![CDATA[SELECT id, city, street FROM address WHERE $P!{whereClause} ORDER BY city]]>
</queryString>

<?xml version="1.0" encoding="UTF-8"?>
<jasperReport xmlns="http://jasperreports.sourceforge.net/jasperreports" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports http://jasperreports.sourceforge.net/xsd/jasperreport.xsd" name="optional_where_clause" language="groovy" pageWidth="595" pageHeight="842" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="d3648644-0087-4dfc-ac6d-87e82d9bb33e">
    <parameter name="inputParamCity" class="java.lang.String"/>
    <parameter name="whereClause" class="java.lang.String" isForPrompting="false">
        <defaultValueExpression><![CDATA[($P{inputParamCity} == null || $P{inputParamCity}.isEmpty()) ? "1=1" : "city='" + $P{inputParamCity} + "'"]]></defaultValueExpression>
    </parameter>
    <queryString>
        <![CDATA[SELECT id, city, street FROM address WHERE $P!{whereClause} ORDER BY city]]>
    </queryString>
    <field name="ID" class="java.lang.Integer"/>
    <field name="CITY" class="java.lang.String"/>
    <field name="STREET" class="java.lang.String"/>
    <detail>
        <band height="20" splitType="Stretch">
            <textField>
                <reportElement uuid="c2a80b99-e087-4839-8e77-841edd899255" x="0" y="0" width="100" height="20"/>
                <textElement/>
                <textFieldExpression><![CDATA[$F{ID}]]></textFieldExpression>
            </textField>
            <textField>
                <reportElement uuid="0aafcfd6-60f7-4272-8e7d-0aa77507204b" x="100" y="0" width="100" height="20"/>
                <textElement/>
                <textFieldExpression><![CDATA[$F{CITY}]]></textFieldExpression>
            </textField>
            <textField>
                <reportElement uuid="c8726513-8250-43ec-bafc-003e81094c27" x="200" y="0" width="100" height="20"/>
                <textElement/>
                <textFieldExpression><![CDATA[$F{STREET}]]></textFieldExpression>
            </textField>
        </band>
    </detail>
</jasperReport>

SELECT id, city, street FROM address WHERE 1=1 ORDER BY city

例如，如果我们为inputParamCity参数设置值Chicago，结果将是：

在本例中，引擎使用的查询是：

SELECT id, city, street FROM address WHERE city='Chicago' ORDER BY city

备注：