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Partial Indexes

1. Introduction

2. Creating Partial Indexes

2.1. Unique Partial Indexes

3. Queries Using Partial Indexes

4. Supported Versions

1. Introduction

A partial index is an index over a subset of the rows of a table.

In ordinary indexes, there is exactly one entry in the index for every row in the table. In partial indexes, only some subset of the rows in the table have corresponding index entries. For example, a partial index might omit entries for which the column being indexed is NULL. When used judiciou

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