TurboDB Engine Documentation

Database Files

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This topic explains the files that make up a TurboDB database. They are named after the file extension used. If you are working with a single-file database, you cannot see these file names directly. But when using the dataweb Compound File Explorer, you will see that the database file contains storage objects (also sometimes called files) with the same name extensions.

dat and rel Files

Contain the database tables, that is the records. Rel files are special database tables created transparently to implement many-to-many relationship. Deploy with your application.

mmo and blb Files

These are the memo and blob files, that exist once for each table that has at least one memo field or at least on blob field. One such file contains all the data of all the memo or blob fields in the table. Deploy with your application.

ind Files

User defined index. Each ind file contains one index. Deploy with your application.

id, inr and in? Files

Automatically generated indexes for tables of level 3 and below. The inr file is an index on the AutoInc field and the id file is an index on its indication. The in? indexes (in0, in1 etc) index link columns. Deploy with your application.

net, rnt, mov and rmv Files

These are the lock files and exist for each table open in shared mode. Do not deploy with your application since these files contain only dynamic information. When your application crashes or is reset during debugging these files happen to remain on your harddisk and will lead to error messages like "table is in use by another application". In this case, just connect to the database with TurboDB Viewer or any other TurboDB application, view the corresponding tables and the files will be deleted when you close this application.

tra and rtr Files

These files are the redo log files for transactions. During an transaction, there is one tra file (rtr for relation tables) for each table modified during the transaction. When the transaction is finished, those files are deleted. If you see those files with your database, when no application is currently accessing it, this means, an application crashed during a transaction. Do not delete the redo logs then, the application that accesses the database tables next, will rollback the interrupted transaction to restore database integrity.

Temporary tables and indexes

Temporary tables have random file names like jzbgopqw.dat and the temporary indexes are called appropriately. These files are usually stored in the user's temporary directory. But you can define any other directory using the PrivateDir property in one of the library components.

tdbd Files

tdbd stands for TurboDB database. Such a file contains all tables and indexes, which belong to a database, if the database was created as a single-file database. In this case there are no real dat, mmo, blb, rel, id, in? and ind files seen in the file system, because the respective data is stored within the tdbd file.