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new GroupSave().assignName("a:b:c").assignDescription("new description").assignReplaceAllSettings(false).save();
To edit just one field (the idIndex) for existing group a:b:c
Note, that new idIndex cant be in use by another group (query grouper_groups_v for the id_index col) and should not be above the current pointer (which you can adjust in the table grouper_table_index)
new GroupSave().assignName("a:b:c").assignIdIndex(12345).assignReplaceAllSettings(false).save();
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