| --- |
| title: Schemas |
| url: schemas |
| aliases: |
| - "tables/schemas" |
| menu: |
| main: |
| parent: Tables |
| identifier: tables_schema |
| weight: 0 |
| --- |
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| |
| # Schemas |
| |
| Iceberg tables support the following types: |
| |
| | Type | Description | Notes | |
| |--------------------|--------------------------------------------------------------------------|--------------------------------------------------| |
| | **`boolean`** | True or false | | |
| | **`int`** | 32-bit signed integers | Can promote to `long` | |
| | **`long`** | 64-bit signed integers | | |
| | **`float`** | [32-bit IEEE 754](https://en.wikipedia.org/wiki/IEEE_754) floating point | Can promote to `double` | |
| | **`double`** | [64-bit IEEE 754](https://en.wikipedia.org/wiki/IEEE_754) floating point | | |
| | **`decimal(P,S)`** | Fixed-point decimal; precision P, scale S | Scale is fixed and precision must be 38 or less | |
| | **`date`** | Calendar date without timezone or time | | |
| | **`time`** | Time of day without date, timezone | Stored as microseconds | |
| | **`timestamp`** | Timestamp without timezone | Stored as microseconds | |
| | **`timestamptz`** | Timestamp with timezone | Stored as microseconds | |
| | **`string`** | Arbitrary-length character sequences | Encoded with UTF-8 | |
| | **`fixed(L)`** | Fixed-length byte array of length L | | |
| | **`binary`** | Arbitrary-length byte array | | |
| | **`struct<...>`** | A record with named fields of any data type | | |
| | **`list<E>`** | A list with elements of any data type | | |
| | **`map<K, V>`** | A map with keys and values of any data type | | |
| |
| Iceberg tracks each field in a table schema using an ID that is never reused in a table. See [correctness guarantees](../evolution#correctness) for more information. |
