![]() Next, let's take a look at what happens when there is some activity (inserts/updates/selects) on the table while the index is being rebuilt. The extra reads and writes can be attributed to the second copy of the index that SQL Server creates during the initial phase of the index rebuild. It's pretty obvious from these results that the ONLINE index rebuild does not perform even close to as well as when run in OFFLINE mode as it uses considerably more resources to complete the rebuild. This initial baseline test used the following commands and were run without any other concurrent activity on the table. SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF,ĭROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON,įor this performance test I first compared the traditional OFFLINE index rebuild with using the ONLINE parameter for both a clustered and a no clustered index rebuild. WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, ![]() IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON,ĬREATE NONCLUSTERED INDEX ON. )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, You can read more on rebuilding indexes here.ĬONSTRAINT PRIMARY KEY CLUSTERED The first rebuilds a single index on a table and the second rebuilds all the indexes on the table. SQL Server ALTER INDEX SyntaxThe syntax for rebuilding indexes is very simple, we just add the "WITH ONLINE=ON" clause to the ALTER INDEX command. the index is no clustered and the index itself contains a LOB database column(s).the index is clustered and the table contains a LOB database column(s).Finally, this option is not available if: Second, we should note that in SQL Server 2005 the online option for index rebuilds is only available in Enterprise edition while in SQL Server 2008 it is available in Enterprise, Developer, and Evaluation editions. If you would like to learn more about the differences between the two operations you can read more here. This tip is going to focus on rebuilds only. First, I want to make sure you understand the difference between rebuilding and reorganizing an index. There are a few things I want to mention regarding online index rebuilds before we get into the details. For an ArcGIS Server installation on Linux, create a cron text file that contains information on the day and time you want the script to run, and load the file into cron using the crontab program.įor example, the following information sets the Python script (named rsysidxdb2.py) to run every Wednesday at 10:00 p.m.: 0 22 * * 3 /usr/bin/rsysidxdb2.pySee the Linux man pages provided with your Linux installation for information on using cron.Solution SQL Server Online Index Rebuild Background Information.When asked what program to run, browse to your Python script. On Windows, open Scheduled Tasks from the Control Panel and use the wizard to add a scheduled task.After you alter the script to contain your connection information, schedule the script to run at a specific time each night.# Usage: out_folder_path, out_name, database_platform, instance, account_authentication, username, password, save_user_passĪrcpy.CreateDatabaseConnectionFile_management(temp, "connection.sde", platform, instance, account_authentication, username, password, saveUserInfo)Īrcpy.RebuildIndexes_management(Connection_File_Name, "SYSTEM", "", "ALL") Print ("Creating Database Connection File.") ![]() SaveUserInfo = "SAVE_USERNAME" #DO_NOT_SAVE_USERNAME #Variable defined within the script other variable options commented out at the end of the line #Leave username and password blank if using OPERATING_SYSTEM_AUTHĬonnection_File_Name = temp + slashsyntax + "connection.sde" # and mv_tables_modified tables in an enterprise geodatabaseĪccount_authentication = OPERATING_SYSTEM_AUTH | DATABASE_AUTH # Description: Rebuilds indexes on the states, state_lineages, To rebuild indexes on the STATES, STATE_LINEAGES, and MVTABLES_MODIFIED geodatabase system tables using the Rebuild Indexes tool, do the following: To do that, create a stand-alone Python script that calls the Rebuild Indexes tool and schedule it to run using Windows Scheduled Tasks or a cron job. In a heavily edited geodatabase that uses traditional versioning, you might update indexes on the STATES, STATE_LINEAGES, and MVTABLES_MODIFIED tables nightly. As the geodatabase administrator, you can rebuild the indexes on these tables in enterprise geodatabases using the Rebuild Indexes geoprocessing tool. Most of the geodatabase system tables have indexes, but the tables that tend to have the greatest amount of change in an enterprise geodatabase that uses traditional versioning and, therefore, require the indexes to be rebuilt most often are the STATES, STATE_LINEAGES, and MVTABLES_MODIFIED system tables. The database uses indexes to quickly identify rows when a client queries the database. Available with Standard or Advanced license.
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