準備
EntityFramework 6
System.Data.SQLite.EF6
SQLite.CodeFirst
設置
app.config
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<configSections>
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</configSections>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.2" />
</startup>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
<parameters>
<parameter value="v13.0" />
</parameters>
</defaultConnectionFactory>
<providers>
<provider invariantName="System.Data.SQLite" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
<provider invariantName="System.Data.SQLite.EF6" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
</providers>
</entityFramework>
<system.data>
<DbProviderFactories>
<remove invariant="System.Data.SQLite.EF6" />
<add name="SQLite Data Provider (Entity Framework 6)" invariant="System.Data.SQLite.EF6" description=".NET Framework Data Provider for SQLite (Entity Framework 6)" type="System.Data.SQLite.EF6.SQLiteProviderFactory, System.Data.SQLite.EF6" />
<remove invariant="System.Data.SQLite" />
<add name="SQLite Data Provider" invariant="System.Data.SQLite" description=".NET Framework Data Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
</DbProviderFactories>
</system.data>
</configuration>
讀取DB
public class MyContext : DbContext
{
public MyContext(DbConnection conn)
: base(conn, true)
{
}
使用CodeFirst寫入DB
class MyContext : DbContext
{
public MyMdContext(DbConnection conn)
:base(conn, true)
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
var sqliteConnectionInitializer = new SqliteCreateDatabaseIfNotExists<MyContext>(modelBuilder);
Database.SetInitializer(sqliteConnectionInitializer);
base.OnModelCreating(modelBuilder);
}
}
數據映射
如果key類型爲整形,必須使用Int64。Sql數據庫中,INT爲32位,INTEGER爲64位
(1) EF創建表的時候,整形的key爲Int64,即使定義的爲int
(2) EF讀取表的時候,若定義的key爲INT,則用int,若INTEGER,則爲Int64
故定義KEY,必須使用INTEGER。EF不會把數據庫中int類型映射爲Int64
輸入插入
默認情況下,每次插入數據都會建立索引,故隨着插入數據增多,會越來越慢。所以需要關閉此功能:
context.Configuration.AutoDetectChangesEnabled = false;
在context.SaveChanges的時候建立一次索引即可。