Description

The @SystemCatalog system procedure returns information about the schema of the VoltDB database, depending upon the component keyword you specify. The following are the allowable values of component:

Return Values

Returns a different VoltTable for each component. The layout of the VoltTables is designed to match the corresponding JDBC data structures. Columns are provided for all JDBC properties, but where VoltDB has no corresponding element the column is unused and a null value is returned.

For the COLUMNS component, the VoltTable has the following columns:

For the FUNCTIONS component, the VoltTable has the following columns:

For the INDEXINFO component, the VoltTable has the following columns:

For the PRIMARYKEYS component, the VoltTable has the following columns:

For the PROCEDURECOLUMNS component, the VoltTable has the following columns:

For the PROCEDURES component, the VoltTable has the following columns:

For the ROLES component, the VoltTable has the following columns:

For the TABLES component, the VoltTable has the following columns:

For the TASKS component, the VoltTable has the following columns:

For the USERS component, the VoltTable has the following columns:

Examples

The following example calls @SystemCatalog to list the stored procedures in the active database schema:

$ sqlcmd
1> exec @SystemCatalog procedures;

The next program example uses @SystemCatalog to display information about the tables in the database schema.

VoltTable[] results = null;
try {
     results = client.callProcedure("@SystemCatalog",
               "TABLES").getResults();
     System.out.println("Information about the database schema:");
     for (VoltTable node : results) System.out.println(node.toString());
}
catch (Exception e) {
     e.printStackTrace();
}