Type Mapping

PG2 provides the following bridge between Postgres and Clojure realms.

Builtin Types

Numbers

Postgres	Reading	Writing
int2	Short	Short, Integer, Long
int4	Integer	the same
int8	Long	the same
numeric	BigDecimal	Most numeric types
float4	Float	Float, Double
float8	Double	the same

Text

Postgres	Reading	Writing
varchar	String	String, UUID, Symbol, Character
text	String	the same
name	String	the same
bpchar	String	the same
regproc	String	the same
char	Character	Character, 1-char String

Geometry

See the Geometry (line, box, etc) section for more info.

Postgres	Reading	Writing
point	Clojure map	Clojure map/vector, SQL string
line	the same	the same
box	the same	the same
circle	the same	the same
polygon	the same	the same
path	the same	the same
lseg	the same	the same

Misc

Postgres	Reading	Writing
uuid	UUID	UUID, String
json	any Clojure value	any Clojure value
jsonb	the same	the same
bytea	byte[]	byte[], ByteBuffer
boolean	Boolean	Boolean
bit	String	byte[], String

Date & Time

Postgres	Reading	Writing
timestamptz	OffsetDateTime	Most Temporal types (OffsetDateTime, Instant, etc)
timestamp	LocalDateTime	the same
date	LocalDate	the same
time	LocalTime	LocalTime, LocalTime
timetz	OffsetTime	OffsetTime, LocalTime

Arrays

PG2 supports arrays of all types mentioned above. They can have more than one dimension which is useful sometimes for storing matrices. Names of array types always start with an underscore: _int4, for example (an array of int4).

For details, read the Arrays Support section.

The table below renders only a small subset of supported arrays:

Postgres	Reading	Writing
_int2	Vector of short	List of short/int/double
_uuid	Vector of UUID	List of UUID
_timestamptz	Vector of OffsetDateTime	List of OffsetDateTime
... (many of them)

Extensions

PG Vector

See PGVector Support.

Postgres	Reading	Writing
vector	Vector of doubles	Vector, List
sparsevec	Clojure map	Vector, Clojure map

Enums

In Postgres, any enum type created in runtime gets its own id. That causes some problems because, although it's nothing but text, its id differs from the standard text type.

Each enum creates two types, in fact. The first one is an enum itself, and the second is an array type. PG2 supports both of them.

For details, see the Reading Postgres Types In Runtime section.

Postgres	Reading	Writing	Comment
foo	String	String, Keyword, Symbol	A plain enum value
_foo	Clojure map	Vector, Clojure map	Array of enum values