Accessing VSTs with ABL or SQL

You can write ABL or SQL to query the information contained in the Virtual System Tables. However, because of the leading underscore (_) in the table names, and field or column names, quotes must be used when writing SQL queries. The following ABL and SQL statements both determine the enabled features of a database from the _database-Feature VST:

Table 1. ABL query 
FOR EACH _database-Feature: 
     IF _DBFeature_Enabled = "1" THEN
     DISPLAY _DBFeature_Name.
Table 2. SQL query 
SELECT 
"_DBFeature_name" FROM pub."_database-Feature" 
     WHERE "_DBFeature_Enabled" = 1;

The result of running either query against the sports database is:

_DBFeature_Name
------------------------
64 Bit DBKEYS
Large Keys
64 Bit Sequences

See the sections that follow for descriptions of the Virtual System Tables and their fields.