如何在groovy中编写字段值可以为null或不为null的查询 公共布尔值IsDuplicateAccountMaterChartOfcountsBySQL（MasterChartOfcounts MasterChartOfcounts）{ 字符串查询：“” 挑选 计数（mcoa.id）为mcoaCount 来自mcoa账户的主图表 哪里 mcoa.parent\u account\u id=${masterchartofcounts.parentAccount？.id} 和mcoa.account_code='${masterchartofcounts.accountCode}' 和mcoa.country_id=${masterchartofcounts.countryId} 和mcoa.account_status_id=${AccountsConstants.DOMAIN_status_ACTIVE} """ Sql db=新Sql（数据源） List resultList=db.rows（查询） 返回resultList.get（0）.mcoaCount }

此处，字段parent\u account\u id可以为NULL，也可以不为NULL。但sql查询不能以这种方式处理空值。我们必须写作 其中mcoa.parent\u account\u id为空。 那么，在字段可以为NULL或不为NULL的情况下，我该怎么办呢

public boolean isDuplicateAccountMaterChartOfAccountsBySQL(MasterChartOfAccounts masterChartOfAccounts) {
    String query = """
        SELECT
            COUNT(mcoa.id) as mcoaCount
            FROM master_chart_of_accounts as mcoa
            WHERE
                mcoa.parent_account_id = ${masterChartOfAccounts.parentAccount?.id}
                AND mcoa.account_code = '${masterChartOfAccounts.accountCode}'
                AND mcoa.country_id = ${masterChartOfAccounts.countryId}
                AND mcoa.account_status_id = ${AccountsConstants.DOMAIN_STATUS_ACTIVE}
        """
    Sql db = new Sql(dataSource)
    List<GroovyRowResult> resultList = db.rows(query)
    return resultList.get(0).mcoaCount
}

公共布尔值是双重AccountMaterChartOfcountsBySQL（MasterChartOfcounts MasterChartOfcounts）{ 字符串查询：“” 挑选 计数（mcoa.id）为mcoaCount 来自mcoa账户的主图表 哪里 mcoa.account_code='${masterchartofcounts.accountCode}' 和mcoa.country_id=${masterchartofcounts.countryId} 和mcoa.account_status_id=${AccountsConstants.DOMAIN_status_ACTIVE} """ if（MasterChartOfcounts.parentAccount？.id）{ query+=“和mcoa.parent\u account\u id=${masterchartofcounts.parentAccount？.id}” } Sql db=新Sql（数据源） List resultList=db.rows（查询） 返回resultList.get（0）.mcoaCount } 是的，我解决了D

    @Transactional(readOnly = true)
public boolean isDuplicateAccountMaterChartOfAccountsBySQL(MasterChartOfAccounts masterChartOfAccounts) {
    String query = """
        SELECT
            COUNT(mcoa.id) as mcoaCount
            FROM master_chart_of_accounts as mcoa
            WHERE
                mcoa.account_code = '${masterChartOfAccounts.accountCode}'
                AND mcoa.country_id = ${masterChartOfAccounts.countryId}
                AND mcoa.account_status_id = ${AccountsConstants.DOMAIN_STATUS_ACTIVE}
        """
    if (masterChartOfAccounts.parentAccount?.id) {
        query += " AND mcoa.parent_account_id = ${masterChartOfAccounts.parentAccount?.id}"
    }
    Sql db = new Sql(dataSource)
    List<GroovyRowResult> resultList = db.rows(query)
    return resultList.get(0).mcoaCount
}