Protobuf support for PostgreSQL
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README.md

pg_protobuf

Protobuf support for PostgreSQL.

Quick start

How to install:

make
make install
make installcheck

Usage example:

create extension pg_protobuf;

create table heroes (x bytea);

-- fill table with random Protobuf data
insert into heroes
  select E'\\x10191880082a060a0200011064822007' ||
         convert_to(substring(md5('' || random() || random()), 0, 8), 'utf-8')
  from generate_series(1,10000);

create function hero_name(x bytea) returns text as $$
begin
return protobuf_get_string(x, 512);
end
$$ language 'plpgsql' immutable;

create function hero_hp(x bytea) returns text as $$
begin
return protobuf_get_int(x, 2);
end
$$ language 'plpgsql' immutable;

create function hero_xp(x bytea) returns text as $$
begin
return protobuf_get_int(x, 3);
end
$$ language 'plpgsql' immutable;

create index hero_name_idx on heroes using btree(hero_name(x));

select hero_name(x) from heroes order by hero_name(x) limit 10;

-- make sure index is used
explain select hero_name(x) from heroes order by hero_name(x) limit 10;

Limitations

Current limitations and possible workarounds:

  • Modification of the Protobuf data is not supported.
  • Enums are not directly supported. However, you can read them using protobuf_get_int and protobuf_get_int_multi procedures;
  • Unsigned Protobuf types (uint, fixed32, fixed64) are not directly supported due to lack of unsigned integer types in PostgreSQL;
  • Attribute [packed=true] for repeated values is not supported by *_multi procedures. However these values can be decoded as raw byte arrays using protobuf_get_bytes* procedures. Warning! In Protobuf 3 values are packed by default unless specified otherwise;