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Data types

The Database API client and the SQLAlchemy dialect use different Python data types. Consult the corresponding section for further information.

Table of contents

Database API client

This section documents data types for the CrateDB Database API client.

Caution

The CrateDB Database API client implementation is incomplete. For the time being, the client uses native Python types.

In general, types are mapped as follows:

CrateDB	Python
boolean	boolean
string	str
int	int
long	int
short	int
double	float
float	float
byte	int
geo_point	list
geo_shape	dict
object	dict
array	list

When writing to CrateDB, the following conversions take place:

Python	CrateDB
Decimal	string
date	integer, long, or string
datetime	integer, long, or string

Note

The type that date and datetime objects are mapped to, depends on the CrateDB column type.

Note

When using date or datetime objects with timezone information, the value is implicitly converted to a Unix time (epoch) timestamp, i.e. the number of seconds which have passed since 00:00:00 UTC on Thursday, 1 January 1970.

This means, when inserting or updating records using timezone-aware Python date or datetime objects, timezone information will not be preserved. If you need to store it, you will need to use a separate column.

SQLAlchemy

This section documents data types for the CrateDB SQLAlchemy dialect.

Type map

The CrateDB dialect maps between data types like so:

CrateDB	SQLAlchemy
boolean	Boolean
byte	SmallInteger
short	SmallInteger
integer	Integer
long	NUMERIC
float	Float
double	DECIMAL
timestamp	TIMESTAMP
string	String
array	ARRAY
object	ObjectType (extension type)
array(object)	ObjectArray (extension type)
geo_point	Geopoint and Geoshape (extension type)
geo_shape	Geopoint and Geoshape (extension type)