enkari / fluentmigrator

fluent migrations for .net

FluentMigrator

Fluent migrations for .NET!

This project’s repository has been moved to the following github repository:

• Project Home: http://www.github.com/schambers/fluentmigrator/

Thanks!

- Sean Chambers

fluentmigrator's Issues

Alter column

It would be nice if there was a way to alter an existing column without deleting and recreating it, for example when you want to change a data type or default value but retain all the data. Maybe something like:

Alter.Column("foo").OnTable("bar").AsInt16().WithDefaultValue(0);

Deleting a column with a default value throws an error in SQL Server

Deleting a column with a default value throws an error in SQL Server, since SQL Server creates a default constraint to enforce the default value. If you are dropping a column, you don't need the default value constrain anymore either, so it should be safe to delete. Here's some code to do it (replace line 71 of SqlServerGenerator.cs with this, if it isn't horribly mangled by the editor):

public override string Generate(DeleteColumnExpression expression)
{
// before we drop a column, we have to drop any default value constraints in SQL Server
string sql = @"
DECLARE @default sysname, @Sql nvarchar(max);

    -- get name of default constraint
    SELECT @default = name 
    FROM sys.default_constraints 
    WHERE parent_object_id = object_id('{0}')
    AND type = 'D'
    AND parent_column_id = (
        SELECT column_id 
        FROM sys.columns 
        WHERE object_id = object_id('{0}')
        AND name = '{1}'
    );

    -- create alter table command as string and run it
    SET @sql = N'ALTER TABLE [{0}] DROP CONSTRAINT ' + @default;
    EXEC sp_executesql @sql;

    -- now we can finally drop column
    ALTER TABLE [{0}] DROP COLUMN [{1}];";

return FormatExpression(sql, expression.TableName, expression.ColumnName);

}

Down() methods not respecting seed_data

When specifying a working directory, it is not looking at the setting in the Down() methods when rolling back

Raw SQL Expression

It may be worthwhile to create an Expressoin that can execute raw sql. Would need to add a new RawExpression and then add it to the ProcessorBase class so that the visitor can traverse it.