How to track changes in SQL Server database?

How to track changes in SQL Server database?

As a part of a Big Data project, we are often asked to find the best way to track the changes applied to the database tables, so that, no requirement is created to load all the huge tables to the data warehouse database at the end of the day, if not all of the data was changed.

How to get the rows count in SQL Server?

There are many ways available in SQL server to get the rows count of each table in SQL server but it would be wise if we find the row count of the table with out writing a query against that table.

How to count the total number of rows across multiple tables?

We can do this with a UNION ALL. This will combine the counts for each table into a single result set. The UNION ALL is important. A UNION does an implicit distinct so any tables with the same number of rows will result in the duplicates being removed.

How to iterate through all tables in a database?

In general, querying the Dynamic Management Views (DMVs), requires VIEW SERVER STATE or VIEW DATABASE STATE permissions based on the Dynamic Management View/Function which is being queried. sp_MSforeachtable is an undocumented system stored procedure which can be used to iterate through each of the tables in a database.

How to track the version of a database?

The method we use for versioning database entries is to use an auditing table. The table has a schema along the lines of: We then have triggers on Insert / Update / Delete of the tables that we want to track.

How does change data capture and change tracking work?

These features enable applications to determine the DML changes (insert, update, and delete operations) that were made to user tables in a database. Change data capture and change tracking can be enabled on the same database; no special considerations are required.

How is source control used to track database changes?

From the moment of linking a database to source control and the initial commit of all SQL database objects, it allows tracking all the changes made against a database that are committed to source control, pulling back any version of a SQL database object and applying it against a database.

How to detect table changes or changes in data?

Then, we can have the web server call the database, say every hour, to see if the hash has changed. If it has, then we will send a new copy of the data to the webserver, which can then in turn submit the data to the client machine (if we are storing it there). Sure beats having to submit the data over and over for every call.

How is change data captured in SQL Server?

SQL Server Change Data Capture uses the SQL Server transaction log as the source of the changed data using asynchronous capture mechanism. Any DML change applied to the tracked table will be written to the transaction log.

What happens if you change the underlying data in a table?

The idea is that, if you change the underlying data you are hashing, then the hash will change. In this case, we are using the hash to say, “This number represents all the data contained ithin this table.” If the data changes, then the hash will change also.

Which is the best way to track changes?

Each record identifies the user who made the change, the date the user made the change, and the actual change, as shown in Figure B. The table is likely to grow quickly, so filters or queries will probably be the most efficient means of using the tracking records. Usually, you can limit the result to a specific record or user.

What are the benefits of track data in a database?

Using change data capture or change tracking in applications to track changes in a database, instead of developing a custom solution, has the following benefits: There is reduced development time. Schema changes are not required. There is a built-in cleanup mechanism. Functions are provided to obtain change information.

When to enable SYSTEM VERSIONING in SQL Server?

System-Versioning can be enabled when a table is created using the CREATE TABLE statement or after creating the table using the ALTER DATABASE statement.

Where do I find change tracking permission in SQL?

Requires the SELECT permission on the primary key columns and VIEW CHANGE TRACKING permission on the table that is specified by the value to obtain change tracking information. The following example shows how to obtain data for an initial synchronization of the table data. The query returns all row data and their associated versions.

How to track the history of data in SQL Server?

The query result will show us the two System_Versioning enabled tables with the Period Start and Period End columns names: SQL Server allows you to add indexes to the temporal and history tables to enhance the query’ performance.