Is MS SQL Server 2017 Supported as Data source?

1. The Appian documentation may not mention it as supported - but that does not mean that it wont work.
2. Appian uses JDBC connectors to connect to the RDBMS.
3. So - as long as the JDBC jar is compatible with MS SQL Server 2017 , it will work.
4. The documentation mentions that MS SQL Server 2016 is supported - so just check if the JDBC jar which Appian installation has - is it compatible with MS SQL Server 2017. You may request the admin to replace the JDBC jar and update the config file.
5. As per Microsoft SQL server documentation you need Microsoft JDBC Driver 6.4 for SQL Server.

6. version 6.2 and 6.4 both should be fine for connecting to SQL Server 2017 https://docs.microsoft.com/en-us/sql/connect/jdbc/microsoft-jdbc-driver-for-sql-server-support-matrix?view=sql-server-2017 

You are correct chetan. we would need at least driver version 6.2 to connect to MS SQL Server 2017.
As eric has mentioned, while it may work, i need to understand the pitfalls of using a non-supported version or am i better off working with the 2016 till 2017 gets supported.

Currently our APPIAN cloud environment has a 6.0 version driver installed.For now, I am going to check with the support team to see if the latest driver could be installed on cloud and what they suggest.

You are correct chetan. we would need at least driver version 6.2 to connect to MS SQL Server 2017.
As eric has mentioned, while it may work, i need to understand the pitfalls of using a non-supported version or am i better off working with the 2016 till 2017 gets supported.

Currently our APPIAN cloud environment has a 6.0 version driver installed.For now, I am going to check with the support team to see if the latest driver could be installed on cloud and what they suggest.