Metadata Editor has two uses – defining pseudo tables and defining DQL.
The foremost and major part of defining a pseudo table is defining a pseudo table based on an existing composite table file (.ctx). Then we can configure the newly-defined pseudo table by setting zone number list, zone expression, user-defined field and so on.
A defined pseudo table can be loaded into the memory and, according to your needs, stored as an in-memory table or a table sequence, for which we can configure options and indexes.
The definition of a pseudo table, in-memory table and table sequence can be exported to a SPL file. Then we generate a SPL script automatically through “defining pseudo tables” functionality for a second editing. This is more convenient than manually defining a pseudo table directly in the SPL script.
The major role of “defining DQL” is to edit DQL tables. Each pseudo table, in-memory table or a table sequence defined in the phase of defining pseudo tables can be converted to a DQL table, and in DQL, they are physical tables. We can define the relationship between DQL tables through “defining DQL” and then perform data queries and search tests on a DQL table.