What is the DBTUNE table?

At its most basic level, the DBTUNE table is a lookup table; when you create data in, or add data to, a geodatabase, ArcSDE looks in the DBTUNE table for the configuration keyword you specify. ArcSDE takes the parameters and configuration strings associated with the keyword and appends them to the CREATE TABLE or CREATE INDEX statements the client application sends to the database. This determines how that table or index gets stored in the database.

For example:

A user named pablo creates a new mines feature class using the New Feature Class wizard in ArcCatalog. Pablo specifies a name for the feature class (mines), field names, types, and lengths. He also specifies the DEFAULTS configuration keyword when creating the feature class and specifies, all the other characteristics of the feature class using the wizard. Because pablo's geodatabase is stored in Oracle, the wizard causes CREATE TABLE and CREATE INDEX statements to be sent to Oracle. ArcSDE searches the DBTUNE table for all records with DEFAULTS as the keyword. It adds the config_string values for each parameter associated with the DEFAULTS keyword to the CREATE TABLE and CREATE INDEX commands sent by the wizard to the database. For the B_STORAGE parameter (which specifies the storage for the business table of the feature class) under DEFAULTS, the statement might be as follows:

CREATE TABLE pablo.mines (OBJECTID NUMBER(38), NAME NVARCHAR2(40), STATUS NUMBER(4)...)
IN TABLESPACE gisdata
WHERE PCTFREE = 0 and INITRANS = 4

Caution:

ESRI does not recommend you use SQL from a SQL editor to directly alter the contents of the DBTUNE table. Doing so would bypass certain protections written into the sdedbtune utility, possibly leading to reduced performance.

The DBTUNE table is created during the postinstallation setup and populated with default keywords, parameter names, and configuration string values or any customized values you made in the dbtune file prior to running the postinstallation tasks. The table contains the following columns:

• keyword—The configuration keyword
• parameter_name—The configuration parameter
• config_string—The value assigned to the configuration parameter

The DBTUNE table in Oracle

Some of the things for which the DBTUNE table is used in Oracle databases include the following:

• Loading tables and indexes into specific tablespaces
• Setting the geometry storage format
  Tip:

  For convenience, four predefined configuration keywords are provided in the installed dbtune.sde file to allow the use of each of the supported geometry storage methods. These are SDELOB, SDO_GEOMETRY, ST_GEOMETRY, and WKB_GEOMETRY.

  During the installation of ArcSDE on Windows, the ArcSDE installation allows you to choose the default spatial storage type. Depending on your selection, ArcSDE will load the DBTUNE table with the contents of one of four files: dbtune.st, dbtune.blob, dbtune.sdo, or dbtune.sde.

• Setting the raster storage format to either BLOB, ST_RASTER, LONGRAW, or the Oracle GeoRaster type
  Tip:

  If all the raster columns in your database use the same raster storage format, set the RASTER_STORAGE parameter once in the DEFAULTS configuration keyword. For example, to change the default RASTER_STORAGE from BLOB to ST_RASTER, the following change is made:

  ## DEFAULTS
  RASTER_STORAGE "ST_RASTER"
  <other parameters>
  END

  Caution:

  Be aware that Oracle has deprecated support of LONGRAW data types. Raster data storage should be converted to ST_Raster, BLOB, or GeoRaster types.

• Indicating whether logging for indexes is enabled
• Specifying how XML document content is stored