如何使用 Entity Framework Core 运行迁移 SQL 脚本

Question

I faced with an issue, where I can't reach the SQL script to apply the migration. Here is my migration code:

 public partial class AddSomethingMigration : Migration
{
    private const string MIGRATION_SQL_SCRIPT_FILE_NAME = @"Migrations\Scripts\20170710123314_AddSomethingMigration.sql";

    protected override void Up(MigrationBuilder migrationBuilder)
    {
        string sql = Path.Combine(Directory.GetParent(Directory.GetCurrentDirectory()).FullName, MIGRATION_SQL_SCRIPT_FILE_NAME));
        migrationBuilder.Sql(File.ReadAllText(sql));
    }
}

So when I use the Package Manager Console on the local machine all works fine. But when I deploy to the environment I get the discrepancy to the file.

Can I run my static SQL scripts via EF migration automatically at all, or I should paste the SQL query inline in code?

Answer 1

I faced with an issue, where I can't reach the SQL script to apply the migration. Here is my migration code:

 public partial class AddSomethingMigration : Migration
{
    private const string MIGRATION_SQL_SCRIPT_FILE_NAME = @"Migrations\Scripts\20170710123314_AddSomethingMigration.sql";

    protected override void Up(MigrationBuilder migrationBuilder)
    {
        string sql = Path.Combine(Directory.GetParent(Directory.GetCurrentDirectory()).FullName, MIGRATION_SQL_SCRIPT_FILE_NAME));
        migrationBuilder.Sql(File.ReadAllText(sql));
    }
}

So when I use the Package Manager Console on the local machine all works fine. But when I deploy to the environment I get the discrepancy to the file.

Can I run my static SQL scripts via EF migration automatically at all, or I should paste the SQL query inline in code?

Answer 2

I faced with an issue, where I can't reach the SQL script to apply the migration. Here is my migration code:

 public partial class AddSomethingMigration : Migration
{
    private const string MIGRATION_SQL_SCRIPT_FILE_NAME = @"Migrations\Scripts\20170710123314_AddSomethingMigration.sql";

    protected override void Up(MigrationBuilder migrationBuilder)
    {
        string sql = Path.Combine(Directory.GetParent(Directory.GetCurrentDirectory()).FullName, MIGRATION_SQL_SCRIPT_FILE_NAME));
        migrationBuilder.Sql(File.ReadAllText(sql));
    }
}

So when I use the Package Manager Console on the local machine all works fine. But when I deploy to the environment I get the discrepancy to the file.

Can I run my static SQL scripts via EF migration automatically at all, or I should paste the SQL query inline in code?

Answer 3

I faced with an issue, where I can't reach the SQL script to apply the migration. Here is my migration code:

 public partial class AddSomethingMigration : Migration
{
    private const string MIGRATION_SQL_SCRIPT_FILE_NAME = @"Migrations\Scripts\20170710123314_AddSomethingMigration.sql";

    protected override void Up(MigrationBuilder migrationBuilder)
    {
        string sql = Path.Combine(Directory.GetParent(Directory.GetCurrentDirectory()).FullName, MIGRATION_SQL_SCRIPT_FILE_NAME));
        migrationBuilder.Sql(File.ReadAllText(sql));
    }
}

So when I use the Package Manager Console on the local machine all works fine. But when I deploy to the environment I get the discrepancy to the file.

Can I run my static SQL scripts via EF migration automatically at all, or I should paste the SQL query inline in code?

Answer 4

I created an extensions method based on 4lexKislitsyn 's answer. This assumes that your files end with a .sql extension and that it's an embeded resource in whatever project your running the migrations from. You could of course move the .sql part to the Up of your migration but this seemed cleaner to me.

public static class MigrationExtensions
{
    public static void RunSqlScript(this MigrationBuilder migrationBuilder, string script)
    {
        var assembly = Assembly.GetExecutingAssembly();
        var resourceName = assembly.GetManifestResourceNames().FirstOrDefault(x => x.EndsWith($"{script}.sql"));
        using var stream = assembly.GetManifestResourceStream(resourceName);
        using var reader = new StreamReader(stream);
        var sqlResult = reader.ReadToEnd();
        migrationBuilder.Sql(sqlResult);
    }
}

Used as

public partial class AddViews : Migration
{
    protected override void Up(MigrationBuilder migrationBuilder)
    {
        migrationBuilder.RunSqlScript("nameOfMyFile");
    }

    protected override void Down(MigrationBuilder migrationBuilder)
    {

    }
}

Answer 5

I've found that evaluating the sql file name from the provided MigrationAttribute the best approach.

  public class EmbeddedSqlFileMigration : Migration
    {
        protected override void Up(MigrationBuilder migrationBuilder)
        {
            var assembly = Assembly.GetExecutingAssembly();
            var type = GetType();
            var migrationAttribute = type.GetCustomAttribute<MigrationAttribute>();
            if (migrationAttribute == null)
                throw new InvalidOperationException("A migration requires a MigrationAttribute.");

            var sqlResourceFilename = $"{type.Namespace}.{migrationAttribute.Id}.sql";
            var resourceName = assembly.GetManifestResourceNames().FirstOrDefault(r => r == sqlResourceFilename);
            if (resourceName == null)
            {
                throw new FileNotFoundException(
                    $"Embedded resource '{sqlResourceFilename}' was not found in assembly '{assembly.FullName}'.");
            }

            using var stream = assembly.GetManifestResourceStream(resourceName);
            if (stream == null)
            {
                throw new InvalidOperationException(
                    $"Unable to get stream for embedded resource '{sqlResourceFilename}' in assembly '{assembly.FullName}'.");
            }

            using var reader = new StreamReader(stream);
            var sqlResult = reader.ReadToEnd();
            migrationBuilder.Sql(sqlResult);
        }
    }

Answer 6

my tech lead and I were trying to figure out why I hadn't found a simple answer to inserting statements yet. Neither was frustrated at the other, both were frustrated at the lack of simplicity we ran into.

We found:

1. https://www.learnentityframeworkcore.com/raw-sql
2. https://mycodingtips.com/2021/9/20/how-to-run-sql-scripts-in-a-file-using-ef-core-migrations 3.https://www.codeproject.com/Articles/1173837/BulkInsert-with-the-Entity-Framework
3. https://www.yogihosting.com/insert-records-entity-framework-core/

All are valid or a good start, NONE are as simple as this:

1. Generate the insert statements needed
2. Use a GO separator between each
3. Parse the file in a Console Project, count up to 500 Go Separators to make blocks of 500 statements
4. Run each of the blocks making a string of each block and use DbSet.FromRawSQL(block of inserts)

I'll write the approach and post the code once I'm done.

Answer 7

You can create a helper method in same project first:

public static string GetRawSql(string sqlFileName)
{
    var baseDirectory = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Migrations");
    var path = Path.Combine(baseDirectory, sqlFileName);
    return File.ReadAllText(path);
}

And then add your migration. Let's say you added as: add-migration AddDefaultUser and then it generated as below:

now add 2 sql files (incuding the SQL statement you want to run like an insert record etc..) with same name with postfix of _Up and _Down. So it will be like:

Then in your migration file UP and DOWN methods, call them by using MigrationBuilder object. So your migration file will look like below:

public partial class AddDefaultUser : Migration
{
    protected override void Up(MigrationBuilder migrationBuilder)
    { 
        migrationBuilder.Sql(SqlFileTrigger.GetRawSql("20220918043843_AddDefaultUser_Up.sql")); 
    }

    protected override void Down(MigrationBuilder migrationBuilder)
    {  
        migrationBuilder.Sql(SqlFileTrigger.GetRawSql("20220918043843_AddDefaultUser_Down.sql"));
    }
}

PS: MAKE SURE YOU SET YOUR SQL FILE PROPERTIES AS COPY ALWAYS TO ENSURE THEY ARE DEPLOYED.

Hope it helps..