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The DATA DICTIONARY keyword |
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| Release 9.3 |    |
NOTE: Present in all ArcSDE geodatabases but can only be altered in geodatabases created under an ArcGIS Server Enterprise license
The DATA_DICTIONARY configuration keyword in the DBTUNE table contains the parameters that define the storage of ArcSDE geodatabase system tables. That means these parameters are read when the geodatabase is created so if you want to modify the storage of these tables, you must alter the dbtune.sde file prior to performing the postinstallation setup, then specify this file when the geodatabase is created. This is especially important on DB2 and Oracle databases because if a specific tablespace is not specified under the DATA_DICTIONARY keyword for certain system tables, these tables will automatically be created in the temporary tablespace on DB2 or the default tablespace of the user (in this case, the ArcSDE administrator's tablespace). Four of the ArcSDE system tables—VERSION, STATES, STATE_LINEAGES, and MVTABLES_MODIFIED—participate in the ArcSDE versioning model and record events resulting from changes made to multiversioned tables. If your site plans to make extensive use of a multiversioned database, these four system tables and their associated indexes will be quite active. In this case, modifying the DATA_DICTIONARY parameters associated with these objects to separate them into their own tablespace allows you to position their data files with data files that experience low I/O activity and thus minimize disk I/O contention. Below is a description of these tables, common to all DBMS implementations, which have the potential to be quite active. An additional table that has the potential to be highly active if you use metadata searches is also described. Knowing what the tables do will help you determine how to store them and their associated indexes.| Table | Description |
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| STATES | Stores change numbers (state IDs) during versioned editing, similar to Oracle SCNs. Contains one row per state ID. Active in a versioned editing environment. May contain thousands to tens of thousands of rows. |
| STATE_LINEAGES | Identifies ordered sequences of state IDs describing chronology of versioned editing. Highly active during versioned editing. May contain millions of rows. |
| VERSIONS | Stores named references to logical groups of edits (versions). Not active. May contain hundreds to thousands of rows. |
| MV_TABLES_MODIFIED | Identifies which tables are edited at each state ID. Active during versioned editing. May contain tens of thousands to hundreds of thousands of rows. |
| SDE_XML_INDEX_TAGS | Defines properties of XPath indexes for metadata searches. Active during content searches by tag and when rebuilding full-text indexes. May contain thousands to tens of thousands of rows, possibly more for large metadata portals. |