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Select Query > Generate MATLAB File to create a file that contains the equivalent Database Toolbox™ functions required to run an existing query that was created in VQB. Edit the file to include MATLAB® or related toolbox functions, as needed. To run the query, execute the file.
The following is an example of a file generated by VQB:
% Set preferences with setdbprefs. s.DataReturnFormat = 'cellarray'; s.ErrorHandling = 'store'; s.NullNumberRead = 'NaN'; s.NullNumberWrite = 'NaN'; s.NullStringRead = 'null'; s.NullStringWrite = 'null'; s.JDBCDataSourceFile = ''; s.UseRegistryForSources = 'yes'; s.TempDirForRegistryOutput = ''; s.FetchInBatches = 'yes'; s.FetchBatchSize = '10000' setdbprefs(s) % Make connection to database. Note that the password has been omitted. % Using ODBC driver. conn = database('dbtoolboxdemo','','password'); % Read data from database. e = exec(conn,'SELECT ALL StockNumber,January,February FROM salesVolume'); e = fetch(e); close(e) Close database connection. close(conn)
The following VQB query elements do not appear in generated files:
Generated code files do not include MATLAB workspace variables to which you assigned query results in the VQB query. The file assigns the query results to e; access these results using the variable e.Data. For example, you can add a statement to the file that assigns a variable name to e.Data as follows:
myVar = e.Data
For security reasons, generated files do not include passwords required to connect to databases. Instead, the database statement includes the string 'password' as a placeholder. To run files to connect to databases that require passwords, substitute your password for the string password in the database statement.