Call For Participation: implement function push down

[Willendless]

We need to push down more functions to maximize TiFlash computation power!

Contributions are welcomed! BTW, it's better to file a PR for every single function.

For more details, please refer to our dev guideline

• part 1: https://pingcap.com/zh/blog/10-minutes-become-a-tiflash-contributor.
• part 2: https://pingcap.com/zh/blog/how-to-implement-a-vectorization-function-in-tiflash

operator functions

func	issue	assignee	pr	progress
LeftShift	#5099	@AnnieoftheStars	#5495	✔︎
RightShift	#5100	@Willendless	#5156	✔︎
BitCount	#5101	@hanzizhao1998	#5101
NullEq	#5102	@JigaoLuo	#6057

string functions

func	issue	assignee	pr	progress
Bin	#5103	@An-DJ	#5246	✔︎
Elt	#5104	@Willendless	#5496	✔︎
BitLength	#5105	@isHuangXin	#6078
Char	#5106	@Ziy1-Tan
HexIntArg/HexStrArg	#5107	@YangKeao	#5280	✔︎
InsertUTF8/Insert	#5108	@lizhenhuan
InstrUTF8/Instr	#5109	@lizhenhuan	#6081
OctInt/OctString	#5110	@Ziy1-Tan	#6064
ReverseUTF8/Reverse	#5111	@lizhenhuan	#5233	✔︎
UnHex	#5112	@b41sh	#5686	✔︎
Space	#5113	@lizhenhuan	#5239	✔︎
Repeat	#5114	@likzn	#5276	✔︎

Cast functions

func	issue	assignee	pr	progress
CastTimeAsDuration	#5306	@AntiTopQuark	#5548	✔︎

Date/Time functions

func	issue	assignee	pr	progress
GetFormat	#5115	@wirybeaver	#5269	✔︎
TimeToSec	#5116	@hey-kong	#5235	✔︎

aggregation functions

func	issue	assignee	pr	progress
Agg_BitOr	#5118	@RinChanNOWWW	#5293

other functions

func	issue	assignee	pr	progress
IsIPv4	#5120	@AntiTopQuark	#6773	✔︎
IsIPv6	#5121	@AntiTopQuark	#6773	✔︎

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23:36:23 UTC+8 Monday, August 15, 2022

[Lloyd-Pottiger]

Maybe you could give an example which will help new hands a lot?

[Willendless]

Maybe you could give an example which will help new hands a lot?

Sure, after we publish an official development guideline, we will add a link here.

[JaySon-Huang]

Maybe mark those issues with the label "help wanted" and remove the "Call for Participation:" from those titles?

[JigaoLuo]

Is the issue be assigned in a first-come-first-serve style?

[ywqzzy]

@Cerdore @mathspanda @johnhaxx7 @fkuner @xiaoshengMr @wzymumon @selectbook @Yxa2111 @raspberry-hu @JialuGong
Hi guys, Thank you for your participation. Do you still have any time to contribute to the issues? Since they are not updated for some time, we want to check if you are still working on them. If you are still working on the issue, please reply "Yes" in 2 days, or I will unassign the tasks. If the tasks are accidentally unassigned, you can assign the tasks again if you are working on it.
Thanks again for your attention!

[An-DJ]

The implementation of Bin in TiDB side had been merged in (pingcap/tidb#37589). @Willendless