You can execute SQL SELECT statements against versioned views to access versioned data.
Read from the Default version
You have two options when running SQL statements against the Default version: you can read the latest or read from a version state you specify.
Read the latest state of the Default version
Versioned views automatically access the current state of the Default version. If you execute SELECT statements against a versioned view, it will access the current state of Default at the time you execute the command. If other users are committing edits to the Default version (thereby changing the state that the Default version references), your subsequent queries will see the latest state and their edits.
Read a specific version state
If you want to query a specific state of the Default version and don't want the state to change while you are querying, execute the sde_set_current_version function. This function validates the supplied version name and sets the corresponding database state internally. If you execute sde_set_current_version for the Default version, queries you make against Default will always point to the state Default referenced when you executed the sde_set_current_version function.
Sde_set_current_version can be executed directly from an SQL client. The syntax is as follows:
SELECT sde.sde_set_current_version('<version_name>');
You can execute this function again to change to return the current state of the versioned table, as needed.
- Be sure there is a versioned view for the versioned feature class or table you want to access.
Beginning with ArcGIS 10.1, versioned views are created when you version data. If your data was registered as versioned prior to 10.1, you can create a versioned view by right-clicking the dataset in the Catalog tree in ArcMap, pointing to Manage, and clicking Enable SQL Access.
- Open a psql client and use the sde_set_current_version function to set the Default version.
SELECT sde.sde_set_current_version('default'); - Issue a SELECT statement against the versioned view to read versioned data from the geodatabase.
In this example, the versioned view is sightings_ev.
SELECT id, species, reporter FROM sightings_ev WHERE reporter = 'chuck';
Read a version other than Default
If you want to query a version other than Default, or you don't want your queries against the Default version to change states, execute the sde_set_current_version function. This function validates the supplied version name and sets the corresponding database state internally. Queries you make against the version will always point to the state the version referenced when you executed sde_set_current_version.
This function can be called again to change to other versions as required and can be called each time the workspace is refreshed to return the current state of the versioned table to the calling application.
- Be sure there is a versioned view for the versioned feature class or table you want to access.
Versioned views are created when you register a table, feature class, or feature dataset as versioned. If your data was versioned prior to ArcGIS 10.1, however, you can create a versioned view by right-clicking the dataset, pointing to Manage, and clicking Enable SQL Access.
- Open a psql client and use the sde_set_current_version function to set the version you want to query.
In this example, fieldinspection is set as the version to be queried.
SELECT sde.sde_set_current_version('fieldinspection'); - Issue a SELECT statement against the versioned view to read versioned data from the geodatabase.
In this example, the versioned view is code_ev.
SELECT owner, site_address, region FROM code_ev WHERE region = 'b';
If you need to return to querying the current state of the Default version, call the set_default function.
SELECT sde.set_default;