本 示例 使用SqlServer2005,先在 数据 库中创建一张表, 其中CustomerId是主键且自动增长;CustomerType用来保存int枚举,字段类型使用int;InsertTime将系统时间作为默认值 CREATE TABLE [ Customer ] ( [ CustomerId ] [ int ] IDENTITY ( 1 , 1 ) NOT NU
本示例使用SqlServer2005,先在数据库中创建一张表,
其中CustomerId是主键且自动增长;CustomerType用来保存int枚举,字段类型使用int;InsertTime将系统时间作为默认值
<span>CREATE</span> <span>TABLE</span> <span>[</span><span>Customer</span><span>]</span><span>( </span><span>[</span><span>CustomerId</span><span>]</span> <span>[</span><span>int</span><span>]</span> <span>IDENTITY</span>(<span>1</span>,<span>1</span>) <span>NOT</span> <span>NULL</span><span>, </span><span>[</span><span>CustomerName</span><span>]</span> <span>[</span><span>nvarchar</span><span>]</span>(<span>50</span>) <span>NOT</span> <span>NULL</span><span>, </span><span>[</span><span>CustomerType</span><span>]</span> <span>[</span><span>int</span><span>]</span> <span>NOT</span> <span>NULL</span><span>, </span><span>[</span><span>Description</span><span>]</span> <span>[</span><span>int</span><span>]</span> <span>NULL</span><span>, </span><span>[</span><span>InsertTime</span><span>]</span> <span>[</span><span>datetime</span><span>]</span> <span>NOT</span> <span>NULL</span> <span>default</span>(<span>getdate</span>()), <span>--</span><span>用于测试在<strong>数据</strong>库中设置默认值</span> <span>CONSTRAINT</span> <span>[</span><span>PK_Customer</span><span>]</span> <span>PRIMARY</span> <span>KEY</span>(<span>[</span><span>CustomerId</span><span>]</span><span>) ) </span><span>ON</span> <span>[</span><span>PRIMARY</span><span>]</span>
接下来创建相应的实体类,可以使用枚举:
<span> public</span> <span>enum</span><span> CustomerType { Home, Abroad } [Table] </span><span>public</span> <span>class</span><span> Customer { [Column(IsPrimaryKey</span>=<span>true</span><span>)] [SqlServerColumn(IsIdentity</span>=<span>true</span>)]<span>//</span><span>针对SqlServer特有的标识列</span> <span>public</span> <span>int</span> CustomerId { <span>get</span>; <span>set</span><span>; } [Column] </span><span>public</span> <span>string</span> CustomerName { <span>get</span>; <span>set</span><span>; } [Column] </span><span>public</span> CustomerType CustomerType { <span>get</span>; <span>set</span><span>; } [Column] </span><span>public</span> <span>string</span> Description { <span>get</span>; <span>set</span><span>; } [Column] [SqlServerColumn(GenerateInsert</span>=AttributeBoolean.False)]<span>//<strong>数据</strong>库中已有默认值,</span><span>告诉Titan在生成Insert语句时不要包含本列</span> <span>public</span> DateTime InsertTime { <span>get</span>; <span>set</span><span>; } }</span>
使用Titan往数据库中添加一条记录:
<span> class</span><span> Program { </span><span>static</span> <span>void</span> Main(<span>string</span><span>[] args) { IDbSession se </span>=<span> OpenDbSession(); Customer customer </span>= <span>new</span><span> Customer(); customer.CustomerName </span>= <span>"</span><span>customer name</span><span>"</span><span>; customer.CustomerType </span>=<span> CustomerType.Abroad; se.Insert(customer); Console.WriteLine(</span><span>string</span>.Format(<span>"</span><span><strong>执行</strong>Insert后标识列返回的CustomerId={0}</span><span>"</span><span>,customer.CustomerId)); se.Close(); Console.ReadLine(); } </span><span>static</span><span> IDbSession OpenDbSession() { </span><span>//</span><span>使用SqlServer。如果是其它<strong>数据</strong>库则可以使用:OracleSqlProvider,MySqlSqlProvider,SQLiteSqlProvider...</span> Type providerType = <span>typeof</span><span>(SqlServerSqlProvider); </span><span>//</span><span><strong>数据</strong>库连接支付串</span> <span>string</span> connectionString = <span>@"</span><span>Data Source=192.168.17.129\SQLEXPRESS;Initial Catalog=titandemo;User Id=sa;Password=123456;</span><span>"</span><span>; </span><span>//</span><span>sql语句追踪,可以跟踪Titan生成的Sql语句,此处使用控制台中查看生成的Sql语句</span> ISqlTracer[] sqlTracers = <span>new</span> ISqlTracer[] { <span>new</span><span> ConsoleSqlTracer() }; </span><span>return</span><span> DbSessionFactory.CreateAndOpenSession(providerType, connectionString, sqlTracers); } }</span>
查看数据库已经添加成功:
控制台程序运行截屏:
从中可以看到生成的Sql语句中不包含CustomerId列和InsertTime列,
由于CustomerId使用了[SqlServerColumn(IsIdentity=true)]标注,Titan在生成Insert语句时不会包含此列,默认情况下还会在Insert语句中包含set @4=SCOPE_Identity()用以取回数据库自动生成的值。
另外数据库中InsertTime列使用了默认值,并且实体类属性中使用了[SqlServerColumn(GenerateInsert=AttributeBoolean.False)]标注,因此生成的Sql语句中也不包含此列。
关于IsIdentity=true标注,如果在[Column]标注中强制不返回,那么Insert语句中set @4=SCOPE_Identity()语句不会被生成。代码如下(注意红色部分):
<span> [Table] </span><span>public</span> <span>class</span><span> Customer { [Column(IsPrimaryKey </span>= <span>true</span>, <span>ReturnAfterInsert =</span><span><span> AttributeBoolean.False</span>)] [SqlServerColumn(IsIdentity </span>= <span>true</span>)]<span>//</span><span>针对SqlServer特有的标识列</span> <span>public</span> <span>int</span> CustomerId { <span>get</span>; <span>set</span>; }
再运行程序,发现Insert语句中不再包含set @4=SCOPE_Identity(),CustomerId的值仍为0。

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