The migration of Oracle databases to Microsoft SQL Server brings many challenges. One of the most significant is associated with mapping Oracle schema to SQL Server. At the architecture level, the wrong approach will result in significant effort in the future. For example, you may even need to rewrite your app’s entire code from scratch. The problem Oracle database server includes an Oracle database and an Oracle instance. You may learn more about the architecture of the Oracle server here. […]

Mapping Oracle data types to SQL Server data types is often a problem during Oracle to Microsoft SQL Server database code conversions. A tried and trusted solution is to use an SQL Server database code conversion. Another reliable solution is to use SQL Server Migration Assistant. These solutions enable you to automate Oracle database conversions to SQL Server. However, there might be some issues you should consider while using SSMA. For example, by default, SSMA applies the maximum available size […]

A materialized view is an important property of Oracle. SQL Server recreates the same behavior as this materialized view in several ways. Unfortunately, SSMA may have issues with converting this object to SQL Server. It flags certain conditions as an error. In this blog post, we will overview the error O2SS0522. It goes about cases in which the Oracle materialized view includes FLOAT columns, subqueries, GROUP BY or WHERE clauses, MINUS, INTERSECT, UNION, etc. By default, SQL Server Migration Assistant (SSMA) converts Oracle […]

With Oracle table functions, you can define a set of PL/SQL statements in such a way that, when queried, should behave just as a regular query to the table. The table function enables you to manipulate individual collection elements (user-defined object types) in your SQL database code. However, this may create a database migration challenge because  SQL Server Migration Assistant (SSMA) cannot convert Oracle table functions. Instead, it generates a set of the following errors: O2SS0474: Conversion of the user-defined type […]

In Oracle, you can create a foreign key for a table using columns with various data types. Unfortunately, SQL Server Migration Assistant (SSMA) fails to convert them to SQL Server correctly since it does not support such elements. As a result, when you try to convert the Oracle code including the foreign key with the columns of different data types, you will see the following message: «Error O2SS0231: Foreign keys with different types of columns and referenced columns cannot be converted». Read this blog post to find out how […]

The pivot clause is an integral part of the Oracle database. In particular, the pivot_clause of the SELECT statement allows you to write crosstabulation queries. Here you can rotate rows into columns and aggregate data in the rotation process. As an important data warehousing element, pivot rotates a table-value expression. To be more specific, it turns the unique value from one expression column into multiple output columns. Besides, pivot performs aggregations where they are needed on any of the remaining column values […]

In Oracle, database links are important features that enable you to access objects on another database. SQL Server has a direct alternative to this function. It provides a linked server or an OPENQUERY feature that allows you to emulate the database links’ functionality. Unfortunately, SQL Server Migration Assistant (SSMA) fails to convert these links automatically. When you try converting a database link query that refers to remote objects, you get the following error: “O2SS0563: Conversion of database link … is not […]

Preventing clients from overspending is one of our top priorities. Hence, we pay close attention to the cost of Oracle to SQL server migration in order to provide the most economical solutions while keeping the highest level of quality. Over years, we have served many clients and helped them to keep costs under control. For example, we successfully completed an Oracle to SQL Server migration proof of concept project ordered by a governmental organization from South America. While working on the project, […]

Proprietary database features often create significant obstacles for developers. To demonstrate as an example, we will take a look at one of Oracle’s most valuable proprietary features – Oracle Call Interface (OCI). It ensures efficient communication between the database and the application code. Surely, you may use other options for connecting to Oracle. However, once you have committed to OCI, switching to another interface becomes a real headache. Read our new blog post to understand how you can overcome challenges […]

Defining a naming convention for the conversion of packaged procedures and functions is a very important step during migration of Oracle database to Microsoft SQL Server. Experienced architects usually point out that this step is as significant as setting schema and data type mapping. Naming convention should be defined at the beginning of the migration project. Let’s discuss in detail why this step is so important and what type of issues you may experience if not defining naming convention properly. […]

Database migration to Microsoft SQL Server 2019 brings your software data management to a new level. It makes your application more secure, scalable, and customizable. Unfortunately, 44% of digitized businesses state that the lack of technical understanding is one of the main obstacles to successful database modernization. How can they overcome this problem? The solution requires a comprehensive approach and a full understanding of the best practices. We strongly advise to take advantage of the latest version of SQL Server 2019. In […]

Azure SQL Managed Instance (MI) is a highly-efficient Azure service that allows combining the broadest SQL Server database compatibility with numerous benefits of a fully managed PaaS (Platform as a Service). MI provides a much higher degree of capability than Azure SQL Database DTU and vCore service levels. Read this blog post to know the main reasons and implications of migrating to Azure SQL MI. Also, get to know how ABCloudz specialists can help you migrate quickly and efficiently. Why […]