Viacheslav Eremin | Professional Programming, Visual Studio, Visual Basic, Vb.Net, C#, Sql Server, Asp, Asp Net Classic, Asp Net Mvc, Asp Net Core, Blazor .Net, Dot Net, Net Framework, Net Core

The _Tables table tracks all the tables in the database. This includes tables that you may have created for your own custom actions. Query this table to find out if a table exists.
The _Columns table tracks columns in the installation database. Temporary columns are currently not tracked by this table. Query this table to find out if a given column exists.
The _Streams table lists embedded OLE data streams.
The _Storages table lists embedded OLE data storages. The _Validation table. The _Validation table tracks the types and allowed ranges of every column in the database. The
_Validation table is used during the database validation process to ensure that all columns are accounted for and have the correct values. This table is not shipped with the installer database.

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