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SQLines ODBC Driver for Oracle to SQL Server - On the Fly Conversion

SQLines ODBC Driver for Oracle to SQL Server allows you to use your existing Oracle ODBC applications with Microsoft SQL Server and SQL Azure databases without or with minimal changes in the source code.

Why SQLines ODBC

SQLines ODBC driver can be very helpful in Oracle to SQL Server and SQL Azure migration project:

Migration Assessment

Before starting the database and application migration, SQLines ODBC driver allows you to collect:

  • SQL statements executed by application (queries, INSERT, UPDATE, DELETE, procedure calls etc.)
  • Dependencies (referenced tables, columns, views, functions, procedures and packages)
  • Performance metrics for further comparison with SQL Server

If you are not a developer of the application, the driver allows you to quickly understand the workflow of the application, and how it interacts with the database that often not easy to grasp from the source code.

SQLines ODBC driver can be used together with source code assessment tools to provide comprehensive migration assessment. Depending on how long the driver is used and which application use cases (scenarios) are executed, you can collect the most representative or all SQL statements in the application.

Once the SQL statements collected, you can analyze their complexity, assess and convert them using various tools or manually.

Application Migration Assessment

After you have migrated the database, you can use SQLines ODBC driver to send all SQL requests to both Oracle and SQL Server or SQL Azure databases.

The application will still recieve the results returned by Oracle, so it will not fail if there are any unresolved migration issues, but at the same time the driver will collect information how these statements work against SQL Server or SQL Azure to help you:

  • Identify queries requiring conversion
  • Find SQL syntax errors
  • Find run-time errors in stored procedure calls

On the Fly Conversion

Typically, an Oracle ODBC application contains many SQL statements written in Oracle native syntax with many flow-of-control statements, expressions and functions (C/C++, Visual Basic applications i.e.) that are used to generate SQL statements based on the user input or application options.

Identifying and transforming SQL statements (for example, moving ROWNUM from WHERE clause to TOP in SELECT list, or transformation of outer joins) is time consuming as you have to pay attention to the program structure that generates the SQL statement with required conditions (WHERE and ORDER BY clauses i.e.).

The problem is even more complicated if you are an ISV and need to support both Oracle and SQL Server versions of your product.

SQLines ODBC driver can perform SQL conversion on the fly, and dramatically reduce the cost of application conversion.

You can also use it as an intermediate step, when you separate database and application migrations to reduce risk, or speed up time-to-market.

User-Defined Conversion

Although conversion on the fly is customizable, you can specify your own conversion for the entire SQL statements to be used by the driver.