What does a PostgreSQL index look like?
When creating an index on the name field(for example), PostgreSQL saves all of them inside a B-Tree - keys are now represented by names. Each entry in the index consists of a C structure called IndexTupleData, and is followed by a bitmap and a value. Bitmaps record if any of the index attributes in a key are NULL, to save space.
Each IndexTupleData structure contains:
- t_tid: This is a pointer to either another index tuple, or to a database record.
- t_info: This contains information about the index tuple, such as how many values it contains, and whether or not there are null values.
10
31 reads
Similar ideas to What does a PostgreSQL index look like?
B-Trees
PostgreSQL implements several types of indexes, such as btree, hash, gist, spgist. The default and most common type of index is btree. A btree (balanced tree) allows for easier and faster searching. This can be seen in the image above where we search for the key with the value of 53.
Btree...
Read & Learn
20x Faster
without
deepstash
with
deepstash
with
deepstash
Personalized microlearning
—
100+ Learning Journeys
—
Access to 200,000+ ideas
—
Access to the mobile app
—
Unlimited idea saving
—
—
Unlimited history
—
—
Unlimited listening to ideas
—
—
Downloading & offline access
—
—
Supercharge your mind with one idea per day
Enter your email and spend 1 minute every day to learn something new.
I agree to receive email updates