The programs present a familiar face to
the user, and they conceal all the details of the SQL language. If a user wants to know, for example, who is the
RA for Martin Jones, the user shouldn??™t have to worry about specifying the JOIN statement, or even about what
columns appear in what tables.
There are many paradigms for programmatic access. The Microsoft approach with the .NET languages is
one. The JDBC approach is another. PHP has another. In this chapter we will review JDBC as a ???neutral???
approach that is characteristic of the way databases can be accessed from software.
In general, a program will create a connection with a database using a user name and password, just as
a person would. Then the program will send SQL code to the DBMS. The SQL code is the same as would be
issued interactively, but the SQL is stored in character strings inside the program, and then sent to the DBMS
for execution.
In the case of JDBC, there is also a very first step required, which is to load the driver code for connecting
to the database. There are several mechanisms, or types of drivers for JDBC. Some will connect by translating
the calls into another standard called open database connection (ODBC); some will convert the JDBC calls into
the native application programming interface (API) of the DBMS; some will convert the calls into an independent
or vendor-specific network DBMS protocol.
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