if you see this error message, while updating Database version.
Start from 2019.0.1.2 and 2019.1.1.2
User need to update their existing SQL Server 2008 R2 Express to SQL 2012 Express, to applies 'LAG'
The 'LAG' Function can be used in the following version of SQL Server (Transact-SQL)
SQL Server 2017 ,SQL Server 2016, SQL Server 2014 , SQL Server 2012
Therefore Please Update to at least SQL 2012 Express, to continue Update to QnE version 2019.0.1.2 and 2019.1.1.2.