Until yesterday, Tableau Prep Builder 2026.1 could connect to SQL Server tables at normal speed, but now the connection seems so slow that it never loads the data preview. I can't use it this way. I got the same slowness in two different 2025 versions. I saw in a different post about slow connection to Salesforce the suggestion to publish the data; this database is hosted on our network, and I wouldn't want to publish every table to the cloud.
What might have changed yesterday?
#Tableau Prep
1 answer
Hi,
If it suddenly got slow, it’s likely not Prep but SQL/network. Test the same query in SSMS - if it’s slow there too, check DB load, locks, or network/VPN changes. If SSMS is fast, check the drivers or connection settings in Prep.
