Let us learn more on alter index unusable Postgresql with the support of our Postgresql support services at Bobcares.

What is alter index unusable in PostgreSQL?

The “ALTER INDEX… UNUSABLE” command is not directly supported in PostgreSQL. Unlike several other database systems, PostgreSQL does not have a built-in capability for marking an index as useless or manually disabling it.

We may achieve a similar result, though, by removing and rebuilding the index or by utilizing partial indexes.

Strategy

Each strategy is explained below:

1. Dropping and recreating the index:

   We can remove an index and rebuild it later in PostgreSQL to make it temporarily useless. Dropping an index removes it from the database, while rebuilding it rebuilds the index using the specified columns and parameters.

   In PostgreSQL, here’s an example of discarding and rebuilding an index:

   

   We may effectively make the index useless by removing it. However, it’s crucial to remember that deleting an index might have an influence on query performance, thus it should be done with caution.
2. Using partial indexes:

   Creating partial indexes is another way to get comparable capabilities. A partial index is one that contains only a subset of rows that satisfy a specified requirement.

   We can essentially build a “unusable” index by employing a condition that always evaluates to false.

   Here’s how to make a partial index in PostgreSQL:

   

As the criterion 1 = 0 in this example always evaluates to false, the index will not include any rows. As a result, the index is practically “unusable” because it offers no value for query optimization.

We may accomplish a similar result to labeling an index as useless in PostgreSQL by removing and rebuilding the index or utilizing partial indexes with criteria that always evaluate to false.

However, while employing these strategies, it is critical to consider the influence on performance and query optimization.

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Conclusion

To sum up we have now seen how to set up alter index unusable Postgresql with the support of our tech support team.