What is ODBC?

The configuration of ODBC data source is to connect vb and SQL and realize the interaction between vb and database.
ODBC is the abbreviation of OPEN DATABASE CONNECITON, which means open database connection. It is a data access method proposed by Microsoft. As long as the database provides an ODBC driver, The application can access the data in the database in ODBC.
In order to facilitate access to data, the WINDOWS system provides an ODBC data source management tool, which is used to set the name of the data source DSN (DATA SOURCE NAME). The so-called DSN is just a sign of a data source. The purpose of setting it is to facilitate the application to access the data. That is to say, as long as the corresponding DSN is set for a database, the application does not need to care about the location of the database and the driver. , You can directly access the database by DSN.
There are three types of DSN: user DSN, system DSN and file DSN.
User DSN User DSN is only visible to the user who set it, and can only be used on the machine where the DSN is set. System DSN System DSN is visible to all users on the machine, including NT services.
File DSN stores the configuration information of DSN in a file, such a file is called file DSN.