Use planner hints on PostgreSQL

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Restore current hint state when returned from non-hinted query planning.

If no hint is given for the current level query, pg_hint_plan_planner
calls the next level of planner after erasing the
current_hint_state. But it forgot to restore the state before the
planning of the rest part of the current-level query. It is
(a-kind-of) broken by the commit d422966 but overlooked as an
inevitable side-effect of the fix. Get back the behavior by restoring
current_hint_state after returned from the lower level planner with
unhinted query.

Issue: https://github.com/ossc-db/pg_hint_plan/issues/30
Reported-by: higuchi-daisuke

Use proper type for non-integer GUC options.

pg_hint_plan internally preserved numeric options into integer
variable regardless of their types, which leads to unintentional
change of the values. Handle double values in the proper way.

Fix Rows hint parsing

This is a long standing bug that Rows hint with no parameter causees a
crash. Fixed the Rows hint parser.

Give correct query location to generate_normalized_query.

There was a thinko about query_loc of generate_normalized_query which
causes a crash. For example a query is following a sequence of
semicolons (by \; in psql input) longer than the length after the last
placeholder to the end of the query, the function causes assertion
failure. Anyway prepared statements lose that value so we just pass 0
as the query_loc for consistent behavior.

Fix behavior of nested planning

Issue: https://github.com/ossc-db/pg_hint_plan/issues/39

When planning is nested by function call, the hints in the function
should affect the corresponding query. Maybe 9599067 introduced
that. Fix the nested planning behavior.

Fix crash bug caused by plancache invalidation

https://github.com/ossc-db/pg_hint_plan/issues/41

After plancache is invalidated then revaliated, get_query_string
accesses query_list of invalid plansource then crash. Ignore invalid
plancache and get the correct hint string and Query node at the next
planning time during revalidation.

On the way fixing this, a bug related to planner reentrance is
fixed. That fix causes behavioral change for nested
planning. Previously outer-level hint (wrongly) overrides inner-level
query but currenlty outer-level hint no longer affects inner-level
query.

Fix compiling error on Solaris

The 'LDFLAGS+=-Wl,--build-id' option is for rpm building in Linux like
OS. The SunOS is not native support the option
'LDFLAGS+=-Wl,--build-id' . So, we disable this option in SunOS while
compiling.

Committed a bit tweaked version from the orignal.

Fix the previous commit.

The previous commit left a line to be removed. Remove it.

Do null-check of error_context_stack before use

The variable is accessed without null checking when planner is called
in the context of pl/pgsql. Fix it. Back-patched up to pg_hint_plan94.

Reporter: egashira-yusuke
Issue: https://github.com/ossc-db/pg_hint_plan/issues/42
Original-Author: sun-wei <30999182+Dagouhan@users.noreply.github.com>
Original-patch: https://github.com/ossc-db/pg_hint_plan/pull/45/commits/8fe092ef73a9af6cfb41e20717d7cb35aa74fce2

Fix regression tests.

Fix regression tests to work for PG12.

Follow the change in PG12.

Commit 428b260f87 breaks the prior assumptions by adding one more
planning cycle for updates on partitioned tables. Follow the change.

Update core.c based on PG12.0

The following commits changes the original functions in core.c as of
REL_12_0. Took in the changes.

7ad6498fd5a654de6e743814c36cf619a3b5ddb6
45f8eaa8e3031c9cb12deb1b5e294bc052b378f2
f49842d1ee31b976c681322f76025d7732e860f3
7ad6498fd5a654de6e743814c36cf619a3b5ddb6

Fix definition of is_dummy_rel based on changes in community

fix spelling mistakes in file pg_hint_plan.html

Use ParallelHint in ParallelHintCreate()

Silence some compilers

Some compilers seem to complain about the previous patch, that
prev_hint_str is used uninitialized. Actually it is not but move the
initialization code out of the PG_TRY() section so that such compilers
would be quiet.

Correctly handle planner nesting

pg_hint_plan assumed that plpgsql is the only source of nested planner
calls. Actually nested call can be made in any shapes. Most of the
cases doesn't harm but in a special case where pg_dbms_stats makes a
SPI call during query planning, that affects subsequent planner
work. Hints lose effect when pg_dbms_stats searches "locked
statistics" tables while planning the target query.

9.5 is not affected. Back patched back to 9.6.

Follow core's cobe/havor chages

Take in some changes took place in core code.

Commit 608b167f9f has largely changed the behavior around
CTE. Although I didn't confirmed that the all changes are valid as the
test for pg_hint_plan, just took in all plan differences.

Change version to 1.3.4.

Fixed a minor bug of 1.3.3.

Fix condition to regenerate gather paths

Core has additional condition to determine whether to generate gather
paths and pg_hint_plan forgot it. Fix it.

Change version to 1.3.3

Version bumped to 1.3.3. SPEC file is updated.

Fix reverse link of hint_list.html

pg_hint_plan.html and hint_list.html pointed to the Japanese version
of main document. Fixed it.

Fix documentation.

Fixed wrong or stale descriptions, and poor or broken styles of
the documentation.

Include all pg_hint_plan--*.sql files in installation

make install didn't install upgrade scripts. Fix it.

Change copyright year to 2019

Fix content of llvmjit package

The previous release is missing index.bc file and mislocating .bc file
in the llvmjit subpackage. The former is created at make install time
so use the standard make file to rpm-build.

Catch up with the latest master

Some refactoring of header files and commits afb0d0712f and 1db5667bac
of core hit this. Catch up with them.

Call standrad_ProcessUtility when no hook is set

The last commit d5ec243 forgot the case of no previous hook function
in the ProcessUtility hook function. Fix it.

Support prepared statements on extended protocol

However pg_hint_plan doesn't fully consider the extended protocol,
commit c05bb31 accidentially broke the case where an analyzed prepared
statement is executed on extended protocol. This patch fixes that only
for the hints-in-comment case. Hint-table still doesn't work in the
case since query-normalization needs Query, which is not available in
planner_hook.

Remove an useless variable

commit c05bb31 made the variable stmt_name useless. Remove it.