JSONB and UniDac

Discussion of open issues, suggestions and bugs regarding PgDAC (PostgreSQL Data Access Components) for Delphi, C++Builder, Lazarus (and FPC)
Post Reply
Posts: 2
Joined: Sun 16 Mar 2014 16:14

JSONB and UniDac

Post by SDobi » Mon 26 Jan 2015 12:11


I would like to ask if the pgDAC is supporting the new JSONB fieldtype and indexing and querying that json data?

I would like to use PostgreSQL as a partial schema-less database in a new project, which will heavily based on that very field to extend the schema and to be able fast search for various attributes stored in jsonb field.

Another question. To this very purpose i need to buy pgDAC or UniDAC will be sufficent? I would like to buy UniDac to support MySQL, SYBASE ASE and PostgresSQL, but i don't know if that in this case will be enough or i need to buy pgDAC as an additional product.

BTW is there any boundle if someone wants to buy more xxDAC product because the UniDAC is not enough?


Sandor Dobi

Devart Team
Posts: 1119
Joined: Fri 11 Apr 2014 11:47
Location: Alpha Centauri A

Re: JSONB and UniDac

Post by azyk » Tue 27 Jan 2015 12:56

The PostgreSQL JSONB data type is a decomposed binary format. To directly access a field with such type in PgDAC, use TBlobField. Creating indexes for fields with the JSONB type and data querying, in which these indexes are used (including fast search by JSONB field attributes), are supported on the server side, and PgDAC doesn't affect this. See more details about the JSONB type and above capabilities in the PostgreSQL documentation: http://www.postgresql.org/docs/9.4/stat ... -json.html .

UniDAC doesn't support some specific features, that are supported by
- Support for the PostgreSQL notices
- Advanced support of the REFCURSOR type
- Wrapper classes for geometic types support

- TMyServerControl, TMyEmbConnection, TMyBackup components

More details about product features are available by the following links:

If you don't plan to use these specific features of PgDAC and MyDAC, then there is no difference between using them or UniDAC.

Post Reply