Fix decimal values in vinyl spaces when upgrading to 2.10.1

This is an upgrade guide for fixing one specific problem which could happen with decimal values in vinyl spaces. It's only relevant when you're upgrading from Tarantool version <= 2.10.0 to anything >= 2.10.1.

Before 6377 was fixed, decimal and double values in a scalar or number index could end up in the wrong order after the update. If such an index has been built for a space that uses the vinyl storage engine, the index is persisted and is not rebuilt even after the upgrade. If this is the case, the user has to rebuild the affected indexes manually.

Here are the rules to determine whether your installation was affected. If all of the statements listed below are true, you have to rebuild indexes for the affected vinyl spaces manually.

• You were running Tarantool version 2.10.0 and below.
• You have spaces with the vinyl storage engine.
• The vinyl spaces have number or scalar indexes.
• The tuples in these spaces may contain both decimal and double Inf or NaN values.

If this is the case for you, you can run the following script, which will find all the affected indices:

 
../_includes/script_find_indices.rst

The indices requiring a rebuild will be stored in the require_rebuild table. If the table is empty, you're safe and can continue using Tarantool as before.

If the require_rebuild table contains some entries, you can rebuild the affected indices with the following script.

 
../_includes/script_rebuild_indices.rst

The script might fail on some of the indices with the following error: "Cannot rebuild primary index index_name on space space_name. Please, recreate the space manually". If this happens, automatic index rebuild is impossible, and you have to manually re-create the space to ensure data integrity:

1. Create a new space with the same format as the existing one.
2. Define the same indices on the freshly created space.
3. Iterate over the old space's primary key and insert all the data into the new space.
4. Drop the old space.