In the background, when doing an Alter View or Alter View as Script, Toad executes the following to get information about the table in a view
SET FMTONLY ON;
SELECT * FROM tablename
SET FMTONLY OFF;
The problem is that a COMMIT TRAN is issued in between the SET FMTONLY ON and OFF which means it will never be actually run. The COMMIT should be after the SET FMTONLY OFF command. This can cause long term blocking.
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