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SQL Server Migration Assistant (SSMA) can be used for database migration, for example, from Oracle to SQL Server. When transferring data from large tables, you can face performance problems  during the data migration process. This article describes how to make the SSMA data migration faster and proposes actions that can improve the performance.
Allocating Target and [...]

In Oracle, you can write a SELECT statement with aggregate functions (like MAX, MIN or AVG) over a partitioned query result set and specify how data are ordered within a partition. Such queries have the following format:
SELECT column_list,
Aggr_fun(column_name) OVER (PARTITION BY column_name ORDER BY column_name)
AS alias_name
FROM table_name;

SQL Server allows selecting data using aggregate functions with [...]

In this article, I am going to cover the situation when REF CURSOR type is used in output parameter of a stored procedure. Often this method is chosen to return the result set from a procedure to an application. Still, in many cases, the cursor reference can be returned from the stored procedure to outer [...]

Here I will describe the migration of functions created as external C libraries in Oracle.  Usually these Oracle functions are defined as CREATE FUNCTION … AS external library … LANGUAGE C. The above statement publishes an external C library through a call specification.

The similar specification in SQL Server 2005/2008 can be written by means of [...]

As Oracle DBMS_PIPE mechanism has no direct equivalent in SQL Server, we should provide a method of emulating it. This article describes a possible approach to this task.

The DBMS_PIPE package allows two or more sessions in the same instance to communicate between each other. To do that, one user creates a Pipe. This pipe can [...]

SQL*Loader is a command line utility which performs fast loading from one or more files into Oracle tables. The utility processes the source files according to the settings in a special CONTROL file. As a result of SQL*Loader execution, additional files can be created: these include BAD file, where discarded rows are saved and ERROR [...]

This article overviews Oracle Text, which is Oracle integrated full-text retrieval technology, and shows the ways to emulate its functionality in Microsoft SQL Server 2005. In Oracle, the CONTEXT index type is used to index large amounts of text. Similar functionality is implemented as Full-Text Search in SQL Server and full-text indexes are used to [...]

Standard Oracle auditing feature allows capturing many pieces of information about database events. You can track the fact that an event occurred, the time when it occurred, the user who caused the audited event, and which client machine the user was on when the event happened. An audited event can be a user login, a [...]

When migrating Oracle tables to SQL Server, the problem of sequence conversion is one of the most common. Indeed, SQL Server does not have any object even distantly resembling an Oracle sequence, and some tradeoffs are inevitable when you make decisions about the mechanisms to implement its behavior in the target system.
In Oracle, a sequence [...]

Hierarchical query is a one of the most powerful feature supplied by Oracle to retrieve complex hierarchical data from a database. Oracle extended syntax of the SELECT statement allows user to construct compact queries using a set of the keywords, pseudocolumns, operators and functions. The results of the queries are ready to be used [...]