[Opt](function) Optimize the performance of FROM_UNIXTIME

[linrrzqqq]

What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

Before:

mysql> SELECT COUNT(FROM_UNIXTIME(`EventTime`)) FROM hits;
+-----------------------------------+
| COUNT(FROM_UNIXTIME(`EventTime`)) |
+-----------------------------------+
|                          99997497 |
+-----------------------------------+
1 row in set (10.54 sec)

After:

mysql> SELECT COUNT(FROM_UNIXTIME(`EventTime`)) FROM hits;
+-----------------------------------+
| COUNT(FROM_UNIXTIME(`EventTime`)) |
+-----------------------------------+
|                          99997497 |
+-----------------------------------+
1 row in set (5.52 sec)

In from_unixtime, we use cctz::convert to transform an unix timestamp into timezone-specific local time, the calculation formula is as follows: tr.civil_sec + (unix_time-tr.unix_time). This step involves a complex calculation with the addition operator to adjust the civil day accordingly like:

y = 1970; m = 1;
while d > 365:
while d > days_in_century(y):
  d -= days_in_century(y); y += 100;
while d > days_in_4years(y):
  d -= days_in_4years(y); y += 4;
while d > days_in_year(y):
  d -= days_in_year(y);  y += 1;
while d > days_in_month(y,m):
d -= days_in_month(y,m);
if (++m > 12) { y++; m = 1; }
return y, m, d;

Solution:

1. Look up the transitions to adjust the UTCOffset, which can be efficiently cached.
2. Look up the unix_days to civil_days cache to obtain the YMD. This cache stores a 200-year mapping starting from 1970-01-01, utilizing minimal memory.

Pseudo code:

int64_t local_unix = unixtime + UTCOffset;
int64_t days = local_unix / 86400;
int64_t seconds_of_day = local_unix % 86400;
civil_day cd = cache[local_unix];
civil_second cs = civil_second(cd)+ seconds_of_day;

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[Thearas]

Thank you for your contribution to Apache Doris.
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Please clearly describe your PR:

1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
2. Which behaviors were modified. What was the previous behavior, what is it now, why was it modified, and what possible impacts might there be.
3. What features were added. Why was this function added?
4. Which code was refactored and why was this part of the code refactored?
5. Which functions were optimized and what is the difference before and after the optimization?

[linrrzqqq]

run buildall

[hello-stephen]

BE UT Coverage Report

Increment line coverage 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	52.76% (18056/34224)
Line Coverage	37.99% (163725/430950)
Region Coverage	32.38% (124836/385540)
Branch Coverage	33.74% (54568/161729)

[hello-stephen]

BE Regression && UT Coverage Report

Increment line coverage 100% (0/0) 🎉

Increment coverage report
Complete coverage report

Category	Coverage
Function Coverage	71.39% (23935/33529)
Line Coverage	57.80% (248967/430751)
Region Coverage	53.05% (207017/390255)
Branch Coverage	54.66% (88824/162502)

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.

[doris-robot]

ClickBench: Total hot run time: 27.89 s

machine: 'aliyun_ecs.c7a.8xlarge_32C64G'
scripts: https://github.com/apache/doris/tree/master/tools/clickbench-tools
ClickBench test result on commit a1984ded322f665f15078d0531ed113101cc0bcd, data reload: false

query1	0.06	0.05	0.05
query2	0.10	0.05	0.06
query3	0.26	0.10	0.08
query4	1.61	0.12	0.12
query5	0.27	0.26	0.25
query6	1.16	0.66	0.66
query7	0.03	0.03	0.03
query8	0.06	0.05	0.04
query9	0.63	0.53	0.52
query10	0.59	0.57	0.58
query11	0.18	0.11	0.11
query12	0.16	0.12	0.12
query13	0.63	0.61	0.61
query14	1.05	1.02	1.03
query15	0.86	0.84	0.84
query16	0.41	0.40	0.39
query17	1.01	1.03	1.07
query18	0.22	0.20	0.19
query19	1.91	1.86	1.82
query20	0.02	0.01	0.01
query21	15.43	0.17	0.12
query22	5.12	0.06	0.05
query23	15.68	0.26	0.10
query24	2.82	0.63	0.81
query25	0.08	0.06	0.05
query26	0.13	0.15	0.13
query27	0.06	0.05	0.05
query28	5.29	1.15	0.92
query29	12.56	4.01	3.33
query30	0.27	0.15	0.11
query31	2.82	0.60	0.39
query32	3.23	0.55	0.48
query33	2.99	3.09	3.03
query34	15.85	5.20	4.54
query35	4.63	4.59	4.61
query36	0.68	0.51	0.50
query37	0.10	0.07	0.07
query38	0.07	0.04	0.04
query39	0.04	0.03	0.04
query40	0.17	0.13	0.15
query41	0.08	0.03	0.03
query42	0.04	0.03	0.02
query43	0.04	0.04	0.04
Total cold run time: 99.4 s
Total hot run time: 27.89 s