（4.31）sql server中的xml数据操作

关键词：xml数据转为行列方式显示

常规案例：

　　

declare @data xml
declare @h int
set @data='
<bookstore>
<row>
<province_id></province_id>
<code></code>
<name>北京市</name>
</row>
<row>
<province_id></province_id>
<code></code>
<name>上海</name>
</row>
</bookstore>
'

exec sp_xml_preparedocument @h output,@data
select * from openxml(@h,'//row',)
with
(
province_id int,
code Varchar(),
name Varchar()
)
exec sp_xml_removedocument @h

触发器中的XML解析

【1】数据库级别DDL操作监控审计

SQL Server 2005开始支持DDL触发器，它不只限于对CREATE/ALTER/DROP操作有效，支持的DDL事件还有比如：权限的GRANT/DENY/REVOEK, 对象的RENAME, 更新统计信息等等，可通过DMV查看更多支持的事件类型如下：

select * from sys.trigger_event_types
where type_name not like '%CREATE%'
  and type_name not like '%ALTER%'
  and type_name not like '%DROP%'
注意：

1. TRUNCATE不在DDL触发器的事件类型中，SQL Server中将Truncate 归为DML操作语句，虽然它也并不触发DML触发器，就像开启开关的大批量导入操作 (Bulk Import Operations) 一样；

2. DDL触发器中捕获的信息都由EVENTDATA()函数返回，返回类型为XML格式，需要用XQuery来读取；

案例：转自2012示例库，只能数据库级别，不能实例级别

复制代码
use database
go

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
create table databaseLog( [PostTime] datetime,
[DatabaseUser] varchar(500),
[Event] varchar(500),
[Schema] varchar(50),
[Object] varchar(4000),
[TSQL] varchar(4000),
[XmlEvent] xml)

CREATE TRIGGER [ddlDatabaseTriggerLog] ON DATABASE --all server 实例级别
FOR DDL_DATABASE_LEVEL_EVENTS AS　　--DDL_SERVER_LEVEL_EVENTS 实例级别
BEGIN
    SET NOCOUNT ON;

    DECLARE @data XML;
    DECLARE @schema sysname;
    DECLARE @object sysname;
    DECLARE @eventType sysname;

    SET @data = EVENTDATA();
    SET @eventType = @data.value('(/EVENT_INSTANCE/EventType)[1]', 'sysname');
    SET @schema = @data.value('(/EVENT_INSTANCE/SchemaName)[1]', 'sysname');
    SET @object = @data.value('(/EVENT_INSTANCE/ObjectName)[1]', 'sysname')

    IF @object IS NOT NULL
        PRINT '  ' + @eventType + ' - ' + @schema + '.' + @object;
    ELSE
        PRINT '  ' + @eventType + ' - ' + @schema;

    IF @eventType IS NULL
        PRINT CONVERT(nvarchar(max), @data);

    INSERT [dbo].[DatabaseLog]
        (
        [PostTime],
        [DatabaseUser],
        [Event],
        [Schema],
        [Object],
        [TSQL],
        [XmlEvent]
        )
    VALUES
        (
        GETDATE(),
        CONVERT(sysname, CURRENT_USER),
        @eventType,
        CONVERT(sysname, @schema),
        CONVERT(sysname, @object),
        @data.value('(/EVENT_INSTANCE/TSQLCommand)[1]', 'nvarchar(max)'),
        @data
        );
END;

GO

SET ANSI_NULLS OFF
GO

SET QUOTED_IDENTIFIER OFF
GO

--开启/关闭
ENABLE TRIGGER [ddlDatabaseTriggerLog] ON DATABASE
DISABLE TRIGGER [ddlDatabaseTriggerLog] ON DATABASE
GO

--删除
DROP TRIGGER tri_LogServerEvent ON DATABASE;

--添加扩展属性到数据库对象中（即添加数据字典注解）
EXEC sys.sp_addextendedproperty @name=N'MS_Description', @value=N'Database trigger to audit all of the DDL changes made to the AdventureWorks2008R2 database.' ,
@level0type=N'TRIGGER',@level0name=N'ddlDatabaseTriggerLog' GO