问题描述
使用
当指定sourceMigration和targetMigration时,我的初始迁移将被写入,其余的迁移将变为空。
When specifying sourceMigration and targetMigration only my initial migration gets written, the rest of my migrations become empty.
我已经输入了包含重现代码的Microsoft Connect错误报告。
I have entered a bug report on Microsoft Connect containing reproducing code.https://connect.microsoft.com/VisualStudio/feedback/details/731111/migratorscriptingdecorator-in-entity-framework-migrations-does-not-respect-sourcemigration-and-targetmigration
我希望 MigratorScriptingDecorator.ScriptUpdate(from,to)
的行为完全像相应的PM命令
I expect MigratorScriptingDecorator.ScriptUpdate("from", "to")
to behave exactly like the corresponding PM command
PM> Update-Database -Script -SourceMigration from -TargetMigration to
ScriptUpdate应等于更新数据库-Script
?
有没有其他方法从代码生成更新脚本?
Should ScriptUpdate be equivalent to Update-Database -Script
?
Are there any other ways of generating update scripts from code?
推荐答案
如所链接的Microsoft Connect问题所述,问题是在几个 MigratorScriptingDecorator $上重复使用相同的
DbMigrator
c $ c> s。
As noted on the linked Microsoft Connect issue the problem was a reuse of the same DbMigrator
on several MigratorScriptingDecorator
s.
原始代码是
DbMigrator efMigrator = new DbMigrator(new Configuration());
var pendingMigrations = efMigrator.GetLocalMigrations().ToList();
pendingMigrations.Insert(0, "0");
foreach (var migration in pendingMigrations.Zip(pendingMigrations.Skip(1), Tuple.Create))
{
var sql = new MigratorScriptingDecorator(efMigrator).ScriptUpdate(migration.Item1, migration.Item2); // <-- problem here, the efMigrator is reused several times
Console.WriteLine("Migration from " + (migration.Item1 ?? "<null> ") + " to " + (migration.Item2 ?? "<null> "));
Console.WriteLine(sql);
Console.WriteLine("-------------------------------------");
}
MigratorScriptingDecorator
应该在这个循环外被实例化:
the MigratorScriptingDecorator
should be instantiated outside the loop like this:
DbMigrator efMigrator = new DbMigrator(new Configuration());
var pendingMigrations = efMigrator.GetLocalMigrations().ToList();
pendingMigrations.Insert(0, "0");
var scriptMigrator = new MigratorScriptingDecorator(efMigrator); // <-- now only one MigratorScriptingDecorator is created for the DbMigrator
foreach (var migration in pendingMigrations.Zip(pendingMigrations.Skip(1), Tuple.Create))
{
var sql = scriptMigrator.ScriptUpdate(migration.Item1, migration.Item2);
Console.WriteLine("Migration from " + (migration.Item1 ?? "<null> ") + " to " + (migration.Item2 ?? "<null> "));
Console.WriteLine(sql);
Console.WriteLine("-------------------------------------");
}
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