When you create a Cloud SQL instance, you need to make the following key
decisions regarding your instance's configuration:

- [Choose an edition for your instance](https://docs.cloud.google.com/sql/docs/postgres/plan-prepare-overview.md.txt#choose-edition)
- [Choose your instance's machine series and storage option](https://docs.cloud.google.com/sql/docs/postgres/plan-prepare-overview.md.txt#choose-machine-storage)
- [Choose your instance's location](https://docs.cloud.google.com/sql/docs/postgres/plan-prepare-overview.md.txt#decide-location)
- [Decide whether to enable data cache](https://docs.cloud.google.com/sql/docs/postgres/plan-prepare-overview.md.txt#decide-data-cache)

You can select these configurations in any order. However, selecting one option
affects the options available for others. Start your decision-making process by
choosing the most important or least flexible configuration.

For example, if you create a Cloud SQL Enterprise Plus edition instance, then your instance is limited
to the regions available for Cloud SQL Enterprise Plus edition. However, if you create a
Cloud SQL Enterprise edition instance, then you can only choose between the general purpose or
N4 machine series options.

## Choose an edition for your instance

Cloud SQL offers two editions to support your business and application
needs:

- **Cloud SQL Enterprise Plus edition**: offers high performance, availability, and observability for applications. These features extend the core capabilities of Cloud SQL.
- **Cloud SQL Enterprise edition**: offers all core capabilities of Cloud SQL and suits applications with less stringent availability and performance requirements.

The edition you choose affects the region and machine series you can choose
from. For detailed information about each edition and its configurations, see
[Choose a Cloud SQL edition](https://docs.cloud.google.com/sql/docs/postgres/choose-edition.md.txt).

## Choose your machine series and storage option

Cloud SQL offers various machine series. A machine series is a curated
set of processor and hardware configurations optimized for specific
Cloud SQL workloads. The machine series available for your instance
depend on its edition, and the storage option depends on the machine series.

The following table lists the machine series and storage options available for
each edition:

| Cloud SQL edition | Machine series | Storage option |
| [Cloud SQL Enterprise Plus edition](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview.md.txt#enterprise-plus) | [C4A](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview.md.txt#c4a) [C4](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview.md.txt#c4) [C4D](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview.md.txt#c4d) | [Hyperdisk Balanced](https://docs.cloud.google.com/sql/docs/postgres/storage-options-overview.md.txt#hyperdisk) [Hyperdisk Balanced](https://docs.cloud.google.com/sql/docs/postgres/storage-options-overview.md.txt#hyperdisk) [Hyperdisk Balanced](https://docs.cloud.google.com/sql/docs/postgres/storage-options-overview.md.txt#hyperdisk) |
| [Cloud SQL Enterprise Plus edition](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview.md.txt#enterprise-plus) |
|---|---|---|
| [N2](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview.md.txt#n2) | [SSD](https://docs.cloud.google.com/sql/docs/postgres/storage-options-overview.md.txt#ssd) |

The machine series you choose affects the edition, region, and storage option.
For more information about machine series options, see [Choose your machine
series](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview). For more information
about storage options, see [Choose a storage option](https://docs.cloud.google.com/sql/docs/postgres/storage-options-overview.md.txt).

## Choose your instance's location

You can choose any available region for your instance. However, depending on the
Cloud SQL edition and machine series you select, available regions
might be limited.

If you choose your instance's location first, then the region you choose affects
the edition and machine series. For more information about region availability
by edition and machine series, see [Region
availability](https://docs.cloud.google.com/sql/docs/postgres/region-availability-overview).

## Decide to enable data cache

Data cache is enabled by default for Cloud SQL Enterprise Plus edition instances, and
lets your instance store data pages on high-speed local solid-state drives
(SSDs) to accelerate query processing. You can choose to disable
data cache.

For an overview of data cache
and recommendations for workloads that perform best with it, see
[Data cache overview](https://docs.cloud.google.com/sql/docs/postgres/data-cache.md.txt).

## What's next

- [Create an instance](https://docs.cloud.google.com/sql/docs/postgres/create-instance.md.txt).
- [Choose a Cloud SQL edition](https://docs.cloud.google.com/sql/docs/postgres/choose-edition.md.txt).
- [Choose a machine series](https://docs.cloud.google.com/sql/docs/postgres/machine-series-overview.md.txt).
- Learn more about [region availability](https://docs.cloud.google.com/sql/docs/postgres/region-availability-overview.md.txt) for Cloud SQL instances.