Notice the contact number for Leonard Hofstadter has dropped the zero 0 from the contact number. The other contact numbers have not dropped the zero 0 at the beginning. The basic syntax is as shown below.
We will create a dummy table for movie categories for demonstration purposes. The script shown below creates the table. The script shown below helps us to achieve that. Executing the above script inserts all the rows from the categories table into the categories archive table. Note the table structures will have to be the same for the script to work. A more robust script is one that maps the column names in the insert table to the ones in the table containing the data.
If you are pasting, choose Paste from the Edit menu. If an error occurs when you save the row the Query and View Designer displays a message and then returns you to the row you were editing. You can then:. Cancel the edit by pressing ESC. If you press ESC while in a cell that you changed, the changes for that cell are canceled. If you press ESC while in a cell you have not changed, the changes for the entire row are canceled. Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services.
Privacy policy. Skip to main content. This browser is no longer supported. 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. 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. 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 datetime2 value equal to , and the row will be opened.
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 without any change.
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. 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:.
To do that, two Period Start and Period End not-nullable datetime2 columns should be added with all specs specified previously as in the below script:. This includes checking that the Period End time is greater than the Period Start time and that the periods of the different versions of the same row will not overlap. Now the AWBuildVersion table is defined as a temporal table successfully:. The system will hold a schema lock on both the temporal and history table, where these changes will be replicated to the history table.
As we discussed previously, the Period start time will be filled by the system with the transaction start time, and the Period End time will be filled by the system with the maximum datetime2 value keeping the records opened.
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