13th August 2026
Lots of improvements in this one relating to the table.transform() feature, which adds support for complex alter table operations by creating a fresh table, copying across the data and then dropping and replacing the old one.
transform() now preserves a much larger array of edge-case schema definitions, including check constraints, unique constraints and even comments describing the columns.
There are also new introspection properties for check constraints, and a whole lot of other smaller changes.
Includes contributions from Bunlong Heng, ethanhawkes-gif, Rami Abdelrazzaq, nyxst4ck, and ikatyal2110.
(It later turned out 4.2 had a crashing bug, fixed in 4.2.1.)
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