Change the compression state of future index inserts or updates using the index_compression clause.
alter index [[database.][owner].table_name.index_name
set index_compression [= {none | page} ]
index_compression – changing the local index partition's compression state affects only index rows that are newly inserted or updated in the partition.
none – the index page for the specified index is not compressed. Indexes that are specifically created with index_compression = page are compressed.
page – when the page is full, existing index rows are compressed using the page prefix compression. When a row is added, a check is performed to determine whether the row is suitable for compression.
alter index order_line. idx_char
set index_compression = page