February 4, 2020
I recently hit the classic case of trying to add Indexes to a large table. Whilst Entity Framework Core supports creating Indexes online during migrations, not all versions of SQL Server support this.
In the case that your migration contains the code:
migrationBuilder.CreateIndex( name: "IX_TableName_ColumnName" table: "TableName", column: "ColumnName").Annotation("SqlServer:Online", true); This will fail hard on SQL Server Express, which you are likely using for development locally, with the error message “Online index operations can only be performed in Enterprise edition of SQL Server.