Locators in a geodatabase stored in DB2
Locators are datasets that contain a snapshot of the reference data you use for geocoding. They contain information on how an address is standardized, the searching methods used for address matches, and the type of information that is returned when there is a match. For more information on how locators are created and used, see Defining the address locator components and related topics.
Locators in ArcGIS Desktop
If you have created an address locator in your geodatabase, it appears in the Catalog tree with the following icon:
The name of an address locator in a geodatabase in DB2 contains the database name, the name of the owner of the locator, and the name of the locator itself.
For example, a locator, city_streets, owned by user oij, in a geodatabase named infrastructure would be listed as INFRASTRUCTURE.OIJ.city_streets in the Catalog tree.
Locators in an IBM DB2 database
When a locator is created, a corresponding locator dataset table is created in the geodatabase. The locator dataset table contains a snapshot of the locator’s reference data, which includes all the attribute and shape information needed for geocoding, stored in a format optimized for quick information search and retrieval.
After a locator is created, it does not use the original reference data; it refers to the locator dataset table.
Locator dataset table names are the same as locator names but suffixed with _lox. If the locator name contains spaces, the spaces are replaced with an underscore in the locator dataset table name.
The locator dataset table is used as a way to persist a collection of binary data blocks (similar to files) in a database.
Note:You should not modify the contents of the locator dataset table.
<locator_name>_lox
When you create a locator, ArcSDE reads geocoding-specific attributes from the reference feature classes, organizes the data in an efficient proprietary binary structure, and stores a snapshot of the reference data in the locator dataset table. Thus, after the locator is created, it does not use the original reference data but only refers to the locator dataset table. As specified by the EmbedGeocodingRules locator property, the locator may also store a copy of its geocoding rule files in its geocoding index table.
The locator dataset table is used as a way to persist a collection of binary data blocks (similar to files) in a database.
|
Field name |
Field type |
Description |
Null? |
|---|---|---|---|
|
FILEID |
INTEGER |
Identifier of the internal geocoding index data block |
|
|
SEGID |
INTEGER |
Identifier of a subsection (segment) of the internal geocoding index data block |
|
|
DATA |
BLOB |
Binary data of the subsection (segment) of the internal geocoding index data block |
The following is a diagram showing the tables in the database management system (DBMS) involved in a locator. In this example, the CITY_STREETS_LOX table is the locator dataset.
Dashed lines indicate implicit relationships between columns.
- Business table
- STREETSis the name of the business table of the feature class on which the locator is based. The business table is only used when the locator is created or rebuilt. While searching for addresses, the locator uses only data from the locator dataset table. If you make changes to the business table and want these changes to be reflected by the locator, you must rebuild the locator using ArcCatalog.
- LOCATORS table
- When you add a locator to an ArcSDE database, ArcSDE adds a row to the LOCATORS table. Each row in the locators table defines a locator or locator style.
- METADATA table
- When you add a locator to an ArcSDE database, ArcSDE adds a row to the METADATA table for each property of the locator. Each row in the METADATA table defines a single property for a locator. The OBJECT_NAME column is a foreign key to the name column in the LOCATORS table that ArcSDE uses to associate a locator with its properties.
Locators in an XML document
At present, locators are not supported in XML documents. Therefore, if you have locators in your geodatabase and you export your geodatabase to an XML workspace document, then import the XML workspace document to another database, you will have to re-create the locators.