Thread: [FeatureRequest] Base Convert Function
Hi! Is there possibility of having internal base converting function in PgSQL? There are already functions for converting between decimal and hexadecimal notations i think pgsql can be able to convert between number with radixes from 1 to 36 (actually fast (de)encoding base36 is what i need)... thx -- S pozdravem Best regards Tomáš Mudruňka - Spoje.net / Arachne Labs XMPP/Jabber: harvie@jabbim.cz, ICQ: 283782978
2010/12/21 Tomáš Mudruňka <tomas@mudrunka.cz>: > Is there possibility of having internal base converting function in PgSQL? > There are already functions for converting between decimal and hexadecimal > notations i think pgsql can be able to convert between number with radixes > from 1 to 36 (actually fast (de)encoding base36 is what i need)... It should be pretty easy to write such a function in C, perhaps using strtol() or strtoul(). Because PostgreSQL uses an extensible architecture, you could load such a function into your copy of PostgreSQL and use it in your environment even if it weren't part of the core distribution. There are a number of existing "contrib" modules that you can look at for examples of how to do this. Whether or not we'd accept a patch to add such a function to core or contrib, I'm not sure. Nobody's written one yet... -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
Dne 21. prosince 2010 12:48 Robert Haas <robertmhaas@gmail.com> napsal(a): > 2010/12/21 Tomáš Mudruňka <tomas@mudrunka.cz>: >> Is there possibility of having internal base converting function in PgSQL? >> There are already functions for converting between decimal and hexadecimal >> notations i think pgsql can be able to convert between number with radixes >> from 1 to 36 (actually fast (de)encoding base36 is what i need)... > > It should be pretty easy to write such a function in C, perhaps using > strtol() or strtoul(). Because PostgreSQL uses an extensible > architecture, you could load such a function into your copy of > PostgreSQL and use it in your environment even if it weren't part of > the core distribution. There are a number of existing "contrib" > modules that you can look at for examples of how to do this. > > Whether or not we'd accept a patch to add such a function to core or > contrib, I'm not sure. Nobody's written one yet... Most used transformations are available from core now - just need a wrapper function. This functions isn't a clean, - should be based on int, long int or bytea? Pavel > > -- > Robert Haas > EnterpriseDB: http://www.enterprisedb.com > The Enterprise PostgreSQL Company > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers >
On Dec21, 2010, at 12:48 , Robert Haas wrote: > 2010/12/21 Tomáš Mudruňka <tomas@mudrunka.cz>: >> Is there possibility of having internal base converting function in PgSQL? >> There are already functions for converting between decimal and hexadecimal >> notations i think pgsql can be able to convert between number with radixes >> from 1 to 36 (actually fast (de)encoding base36 is what i need)... > > It should be pretty easy to write such a function in C, perhaps using > strtol() or strtoul(). If you're not comfortable doing this in C, you might also want to consider one of procedural languages pl/pgsql, pl/perl, pl/python. pl/pgsql is probably only viable if you just need this for ints and bigints, unless you don't care about performance. best regards, Florian Pflug
Thx for you answers :-) Well... i know that i can write my own plugin and i am familiar with C so this is not the problem, but i think that such feature should be implemented directly in PgSQL because there are already functions for converting to/from base 16 so why don't make this more flexible and generalize it to any other radix? It's quite simple to do and i don't see any reason why 16 should be there and 8, 32 or 36 shouldn't :-) peace On Tue, 21 Dec 2010 15:04:03 +0100, Florian Pflug <fgp@phlo.org> wrote: > On Dec21, 2010, at 12:48 , Robert Haas wrote: >> 2010/12/21 Tomáš Mudruňka <tomas@mudrunka.cz>: >>> Is there possibility of having internal base converting function in >>> PgSQL? >>> There are already functions for converting between decimal and >>> hexadecimal >>> notations i think pgsql can be able to convert between number with >>> radixes >>> from 1 to 36 (actually fast (de)encoding base36 is what i need)... >> >> It should be pretty easy to write such a function in C, perhaps using >> strtol() or strtoul(). > > If you're not comfortable doing this in C, you might also want to consider > one of procedural languages pl/pgsql, pl/perl, pl/python. pl/pgsql is > probably > only viable if you just need this for ints and bigints, unless you don't > care about performance. > > best regards, > Florian Pflug -- S pozdravem Best regards Tomáš Mudruňka - Spoje.net / Arachne Labs XMPP/Jabber: harvie@jabbim.cz, ICQ: 283782978
Hello Dne 21. prosince 2010 21:11 Tomáš Mudruňka <tomas@mudrunka.cz> napsal(a): > > Thx for you answers :-) > Well... i know that i can write my own plugin and i am familiar with C so > this is not the problem, but i think that such feature should be > implemented directly in PgSQL because there are already functions for > converting to/from base 16 so why don't make this more flexible and > generalize it to any other radix? It's quite simple to do and i don't see > any reason why 16 should be there and 8, 32 or 36 shouldn't :-) > * It isn't a typical and often request, * There are not hard breaks for custom implementation, * You can use plperu or plpython based solutions, * It's not part of ANSI SQL Regards Pavel Stehule > peace > > On Tue, 21 Dec 2010 15:04:03 +0100, Florian Pflug <fgp@phlo.org> wrote: >> On Dec21, 2010, at 12:48 , Robert Haas wrote: >>> 2010/12/21 Tomáš Mudruňka <tomas@mudrunka.cz>: >>>> Is there possibility of having internal base converting function in >>>> PgSQL? >>>> There are already functions for converting between decimal and >>>> hexadecimal >>>> notations i think pgsql can be able to convert between number with >>>> radixes >>>> from 1 to 36 (actually fast (de)encoding base36 is what i need)... >>> >>> It should be pretty easy to write such a function in C, perhaps using >>> strtol() or strtoul(). >> >> If you're not comfortable doing this in C, you might also want to > consider >> one of procedural languages pl/pgsql, pl/perl, pl/python. pl/pgsql is >> probably >> only viable if you just need this for ints and bigints, unless you don't >> care about performance. >> >> best regards, >> Florian Pflug > > -- > S pozdravem > Best regards > Tomáš Mudruňka - Spoje.net / Arachne Labs > > XMPP/Jabber: harvie@jabbim.cz, ICQ: 283782978 > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers >
Hello, Pavel. You wrote: PS> Hello PS> Dne 21. prosince 2010 21:11 Tomáš Mudruňka <tomas@mudrunka.cz> napsal(a): >> >> Thx for you answers :-) >> Well... i know that i can write my own plugin and i am familiar with C so >> this is not the problem, but i think that such feature should be >> implemented directly in PgSQL because there are already functions for >> converting to/from base 16 so why don't make this more flexible and >> generalize it to any other radix? It's quite simple to do and i don't see >> any reason why 16 should be there and 8, 32 or 36 shouldn't :-) >> PS> * It isn't a typical and often request, PS> * There are not hard breaks for custom implementation, PS> * You can use plperu or plpython based solutions, PS> * It's not part of ANSI SQL But MySQL has such function. What's wrong with us? ;) PS> Regards PS> Pavel Stehule >> peace >> >> On Tue, 21 Dec 2010 15:04:03 +0100, Florian Pflug <fgp@phlo.org> wrote: >>> On Dec21, 2010, at 12:48 , Robert Haas wrote: >>>> 2010/12/21 Tomáš Mudruňka <tomas@mudrunka.cz>: >>>>> Is there possibility of having internal base converting function in >>>>> PgSQL? >>>>> There are already functions for converting between decimal and >>>>> hexadecimal >>>>> notations i think pgsql can be able to convert between number with >>>>> radixes >>>>> from 1 to 36 (actually fast (de)encoding base36 is what i need)... >>>> >>>> It should be pretty easy to write such a function in C, perhaps using >>>> strtol() or strtoul(). >>> >>> If you're not comfortable doing this in C, you might also want to >> consider >>> one of procedural languages pl/pgsql, pl/perl, pl/python. pl/pgsql is >>> probably >>> only viable if you just need this for ints and bigints, unless you don't >>> care about performance. >>> >>> best regards, >>> Florian Pflug >> >> -- >> S pozdravem >> Best regards >> Tomáš Mudruňka - Spoje.net / Arachne Labs >> >> XMPP/Jabber: harvie@jabbim.cz, ICQ: 283782978 >> >> -- >> Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) >> To make changes to your subscription: >> http://www.postgresql.org/mailpref/pgsql-hackers >> -- With best wishes,Pavel mailto:pavel@gf.microolap.com
On Tue, Dec 21, 2010 at 11:28:17PM +0200, Pavel Golub wrote: > Hello, Pavel. > > You wrote: > > PS> Hello > > PS> Dne 21. prosince 2010 21:11 Tom???? Mudru??ka <tomas@mudrunka.cz> napsal(a): > >> > >> Thx for you answers :-) > >> Well... i know that i can write my own plugin and i am familiar with C so > >> this is not the problem, but i think that such feature should be > >> implemented directly in PgSQL because there are already functions for > >> converting to/from base 16 so why don't make this more flexible and > >> generalize it to any other radix? It's quite simple to do and i don't see > >> any reason why 16 should be there and 8, 32 or 36 shouldn't :-) > >> > > PS> * It isn't a typical and often request, > PS> * There are not hard breaks for custom implementation, > PS> * You can use plperu or plpython based solutions, > PS> * It's not part of ANSI SQL > > But MySQL has such function. What's wrong with us? ;) > You are not really helping to make a good case... :) Ken
On 12/21/2010 04:28 PM, Pavel Golub wrote: > > PS> * It isn't a typical and often request, > PS> * There are not hard breaks for custom implementation, > PS> * You can use plperu or plpython based solutions, > PS> * It's not part of ANSI SQL > > But MySQL has such function. What's wrong with us? ;) > Our aim is not to duplicate everything in MySQL. cheers andrew
Hello. Guys, guys! It was only a joke! :) Please accept my appologies. Anyway I find such function usefull even though I still hadn't situation when it might be needed. You wrote: AD> On 12/21/2010 04:28 PM, Pavel Golub wrote: >> >> PS> * It isn't a typical and often request, >> PS> * There are not hard breaks for custom implementation, >> PS> * You can use plperu or plpython based solutions, >> PS> * It's not part of ANSI SQL >> >> But MySQL has such function. What's wrong with us? ;) >> AD> Our aim is not to duplicate everything in MySQL. AD> cheers AD> andrew -- With best wishes,Pavel mailto:pavel@gf.microolap.com
On Tue, Dec 21, 2010 at 4:57 PM, Pavel Golub <pavel@microolap.com> wrote: > Anyway I find such function usefull even though I still hadn't > situation when it might be needed. Yeah, I agree. I'm not sure we should add it to core, but it's certainly just as useful as many things we have in contrib. I'll bet it would get at least as much use as the six argument form of levenshtein_less_equal(). -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company