# Schemas, storage types and meanings[¶](https://doc.dataiku.com/dss/latest/schemas/index.html#schemas-storage-types-and-meanings "Permalink to this headline")

* Definitions

+ Storage types

- Why use precise storage types ?

+ Meanings

* Basic usage

+ Changing meaning and storage type

- Changing the storage type

- Changing the meaning

- Editing advanced schema

* Schema for data preparation

+ Schema in visual analysis

+ Schema in prepare recipe

* Creating schemas of datasets

+ Schema of new external datasets

- SQL and Cassandra datasets

- Text-based files datasets

- “Typed” files datasets

+ Schema of managed datasets

+ Modifying the schema

* Handling of schemas by recipes

+ Sample, Filter, Group, Window, Join, Split, Stack

+ Sync

+ Prepare

+ Hive, Impala, Pig, SQL

+ Python, R, PySpark, SparkR

+ Machine Learning (scoring)

+ SparkSQL

+ Shell

* List of recognized meanings

+ Basic meanings

- Text

- Decimal

- Integer

- Boolean

- Date / Dates (needs parsing)

- Object / Array

- Natural language

+ Geospatial meanings

- Latitude / Longitude

- Geopoint

- Geometry

- Country

- US State

+ Web-specific meanings

+ Other meanings

* User-defined meanings

+ Kinds of user-defined meanings

- Declarative

- Values list

- Values mapping

- Pattern

+ Autodetecting user-defined meanings

* Handling and display of dates

+ Displaying dates

+ Handling of dates in SQL
