Selects data from a table or multiple tables.GROUP BY groups the the result by the given expressions.HAVING filter rows after grouping.ORDER BY sorts the result.Every big or dynamic website uses a database in some way, and when combined with Structured Query Language SQL, the possibilities for manipulating data really are.Update Using Multiple Tables Sql Commands' title='Update Using Multiple Tables Sql Commands' />How to track the history of data changes using SQL Server 2.System Versioned Temporal Tables.SQL Server 2.This new table type is called a System Versioned Temporal Table.In earlier SQL Server versions, user tables would enable you to hold only the most recent copy of the row, without being able to query the value before the UPDATE or DELETE operations.Using a Temporal Table, you will be able to query the recent state of the row as usual, in addition to the ability to query the full history of that row, which is fully managed by the SQL Server Engine, as you cant define the rows validity period explicitly.Each System Versioned Temporal Table should contain two datetime period columns that are explicitly defined in the table the Period Start column that will be used by the system to store the start time of the row, and the Period End column in which the system will store the end time of the row.The main Temporal table will keep only the current version of the table rows, but it will be linked automatically to another table with the same exact schema, in which the previous versions of the modified rows will be stored automatically, this table is called a History table.When you create a Temporal table, the History table will be created automatically.If you dont specify the history table name as a parameter in the SYSTEMVERSIONING clause, it will be named with the naming pattern MSSQLTemporal.B25329_01/doc/appdev.102/b25108/img/xe_sql_commands.gif' alt='Update Using Multiple Tables Sql Commands' title='Update Using Multiple Tables Sql Commands' />History.Forlt objectid.Specifying the history table name while creating the Temporal table will allow the system to create the history table with the default system configuration, with the ability to create your own history table and provide its name in the Temporal table creation statement.Take into consideration that no changes can be performed on the history tables data.If you try to delete any row from the history table, you will get the Cannot delete rows from a temporal history table lt table.Name error, as it is only managed by the system.When a new row is inserted, the system will assign the Period Start time column with the current transaction start time based on the system clock, and assign the Period End time column with the maximum datetime.If an existing row is updated, the system will copy the previous version of the row in the history table and fill the Period End time column with the current transaction start time based on the system clock, and the row will be closed.The Period End time column value of the main temporal table will be 9.Deleting an existing row, the row will be stored in the history table, with the Period End time column value equal to the current transaction start time based on the system clock, and the row will be closed after deleting it from the main temporal table.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.In order to enable System Versioning in a table, it must have a primary key, with two not nullable datetime.GENERATED ALWAYS AS ROW START or END, passed as parameters in the PERIOD FOR SYSTEMTIME within the table definition.The below CREATE TABLE statement is used to create the TemporalTableDemo temporal table, with Demp.ID primary key, the two period columns Time.Start GENERATED ALWAYS AS ROW START and Time.End GENERATED ALWAYS AS ROW END, both designated as PERIOD FOR SYSTEMTIME, the temporal table is linked to the dbo.TemporalTableDemoHistory history table, taking into consideration that identifying the history table schema name is mandatory, and finally enabling the SYSTEMVERSIONING feature as follows.USE SQLShack.Demo.CREATE TABLE dbo.TemporalTableDemo.Demp.ID int NOT NULL PRIMARY KEY CLUSTERED.Dep.Name nvarchar1.NOT NULL., Dep.Location varchar1.NOT NULL., Num.Of.Emp int NOT NULL.Time.Start datetime.GENERATED ALWAYS AS ROW START.Time.End datetime.GENERATED ALWAYS AS ROW END.PERIOD FOR SYSTEMTIME Time.Start, Time.End.WITH SYSTEMVERSIONING ON HISTORYTABLE dbo.TemporalTableDemoHistory USESQLShack.Demo GOCREATE TABLE dbo.TemporalTableDemo Demp.IDint.NOTNULLPRIMARY KEY CLUSTERED ,Dep.Namenvarchar1.NOTNULL ,Dep.Locationvarchar1.NOTNULL ,Num.Of.Empint.NOTNULL ,Time.Startdatetime.GENERATED ALWAYS ASROW START ,Time.Enddatetime.GENERATED ALWAYS ASROW END ,PERIOD FORSYSTEMTIMETime.Start,Time.Toy Story 1999 Nederlands Gesproken Download .End WITHSYSTEMVERSIONINGONHISTORYTABLEdbo.TemporalTableDemoHistory Browse the new temporal table from the Object Explorer, where you will see a special icon with a small clock see below image for the temporal table with System Versioned between the parentheses.The history table will not have a separate table node it can be shown by expanding the temporal table with a node under the main table identified with History between parentheses.A default clustered index will be created for the history table that contains the two Period Start and Period End columns as below.Lets assume that we need to enable System Versioning on an existing table in our database.To do that, two Period Start and Period End not nullable datetime.ALTER TABLE dbo.AWBuild.Version ADD.Time.Start DATETIME20 GENERATED ALWAYS AS ROW START NOT NULL CONSTRAINT DFTAWBuild.VersionTime.Start DEFAULT 1.Time.End DATETIME20 GENERATED ALWAYS AS ROW END NOT NULL CONSTRAINT DFTAWBuild.VersionTime.End DEFAULT 9.PERIOD FOR SYSTEMTIME Time.Start, Time.End.ALTER TABLE dbo.AWBuild.Version. 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