regex101: SQL - columns to MAX LEN

Regular Expression

\[([^]]*)\]

New

[EtlRowId]
      ,[PartitionKey]
      ,[RowKey]
      ,[Timestamp]
      ,[LoadDTS]
      ,[Microsoft_VSTS_Common_BacklogPriority]
      ,[Microsoft_VSTS_Common_Priority]
      ,[Microsoft_VSTS_Common_ValueArea]
      ,[Microsoft_VSTS_Scheduling_Effort]
      ,[System_AreaPath]
      ,[System_BoardColumn]
      ,[System_BoardColumnDone]
      ,[System_ChangedBy]
      ,[System_ChangedDate]
      ,[System_CommentCount]
      ,[System_CreatedBy]
      ,[System_CreatedDate]
      ,[System_IterationPath]
      ,[System_Reason]
      ,[System_State]
      ,[System_Tags]
      ,[System_TeamProject]
      ,[System_Title]
      ,[System_WorkItemType]
      ,[TeamNowCustomerId]
      ,[fields]
      ,[id]
      ,[projectId]
      ,[projectName]
      ,[rev]
      ,[url]
      ,[Microsoft_VSTS_Common_ClosedDate]
      ,[System_AssignedTo]
      ,[BugIterationHash]
      ,[TeamIterationHash]
      ,[BugHash]

Regular Expressions 101

Regular Expression

Extraction