How do you choose between XMLA and TMSL for SSAS scripting?

1 What is XMLA?

XMLA stands for XML for Analysis, a standard protocol for communicating with analytical data sources using XML. XMLA was the original scripting language for SSAS and is still widely used for creating, modifying, deploying, and processing SSAS objects. XMLA scripts are composed of commands and statements that follow the XMLA schema. You can write and execute XMLA scripts using tools such as SQL Server Management Studio (SSMS), SQL Server Data Tools (SSDT), or PowerShell.

2 What is TMSL?

TMSL stands for Tabular Model Scripting Language, a JSON-based language for scripting SSAS tabular models. TMSL was introduced in SSAS 2016 and is designed to simplify and streamline the scripting of tabular models. TMSL scripts are composed of requests and actions that follow the TMSL schema. You can write and execute TMSL scripts using tools such as SSMS, SSDT, or PowerShell.

3 XMLA vs TMSL: Features

Both XMLA and TMSL can perform similar tasks, such as creating, altering, deploying, processing, and refreshing SSAS objects. However, there are some differences between the two languages. XMLA supports both multidimensional and tabular models, while TMSL only supports tabular models. XMLA uses XML tags and attributes and has more commands and statements than TMSL. On the other hand, TMSL has some actions that are not available in XMLA and allows you to script the entire tabular model definition in a single script. In contrast, XMLA requires multiple scripts for each object type.

4 XMLA vs TMSL: Advantages

XMLA and TMSL both have their advantages depending on the scenario and user preference. XMLA is more mature, stable, and powerful than TMSL, as it has been around longer and can handle more complex scenarios. On the other hand, TMSL is more concise, readable, user-friendly, and intuitive than XMLA, as it uses JSON syntax and follows the tabular model structure. It also avoids the verbosity of XML and can script the whole model in one go.

5 XMLA vs TMSL: Disadvantages

Both XMLA and TMSL have their own set of advantages and disadvantages depending on the scenario and user preference. XMLA is more verbose and complex than TMSL, as it uses XML syntax and requires more code and elements to achieve the same result. Additionally, XMLA is more prone to errors and typos than TMSL, as it relies on case-sensitive tags and attributes and has less validation and feedback. On the other hand, TMSL is less mature and stable than XMLA, as it is relatively new and has less documentation and support. Furthermore, TMSL is less flexible and powerful than XMLA, as it cannot handle some scenarios and features that are only available in XMLA.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?