From f9db29f90c55da98d48c879187f5c1d379293cd7 Mon Sep 17 00:00:00 2001
From: pavel-zotov <p519446@yandex.ru>
Date: Sat, 20 Jan 2024 20:27:52 +0300
Subject: [PATCH] Added/Updated tests\bugs\gh_3218_test.py: Checked on
 6.0.0.218, 5.0.1.1318.

---
 tests/bugs/gh_3218_test.py | 106 +++++++++++++++++++++++++++++++++++++
 1 file changed, 106 insertions(+)
 create mode 100644 tests/bugs/gh_3218_test.py

diff --git a/tests/bugs/gh_3218_test.py b/tests/bugs/gh_3218_test.py
new file mode 100644
index 00000000..3f148ef9
--- /dev/null
+++ b/tests/bugs/gh_3218_test.py
@@ -0,0 +1,106 @@
+#coding:utf-8
+
+"""
+ID:          issue-3218
+ISSUE:       3218
+TITLE:       Optimizer fails applying stream-local predicates before merging [CORE2832]
+DESCRIPTION:
+    We evaluate number of records in rdb$relation_fields for which corresponding rows in rdb$relations have ID < 10.
+    This value ('cnt_chk') must be equal to the number of indexed reads for this table when we run test query ('chk_sql').
+    Before fix number of indexed reads in rdb$relation_fields was equal to the TOTAL number of rows in this table.
+FBTEST:      bugs.gh_3218
+NOTES:
+    [20.01.2024] pzotov
+    Confirmed problem on 5.0.0.442: number of indexed reads was equal to the total count of records in rdb$relation_fields.
+    Checked on 6.0.0.218, 5.0.1.1318.
+"""
+
+import pytest
+from pathlib import Path
+from firebird.qa import *
+
+init_sql = """
+    set term ^;
+    create or alter procedure sp_get_relations returns(
+        rdb$relation_id type of column rdb$relations.rdb$relation_id,
+        rdb$relation_name type of column rdb$relations.rdb$relation_name
+    ) as
+    begin
+        for
+        select
+            rdb$relation_id,
+            rdb$relation_name
+        from rdb$relations
+        into
+            rdb$relation_id,
+            rdb$relation_name
+        do
+        begin
+            suspend;
+        end
+    end
+    ^
+    set term ;^
+    commit;
+"""
+db = db_factory(init = init_sql)
+
+act = python_act('db')
+
+#----------------------------------------------------------
+
+def replace_leading(source, char="#"):
+    stripped = source.lstrip()
+    return char * (len(source) - len(stripped)) + stripped
+
+#----------------------------------------------------------
+
+@pytest.mark.version('>=5.0')
+def test_1(act: Action, capsys):
+    with act.db.connect() as con:
+        cur = con.cursor()
+        cur.execute("select rdb$relation_id from rdb$relations where rdb$relation_name = upper('rdb$relation_fields')")
+        rf_rel_id = None
+        for r in cur:
+            rf_rel_id = r[0]
+        assert rf_rel_id
+
+        cur.execute("select count(iif(r.rdb$relation_id < 10, 1, null)) cnt_chk, count(*) as cnt_all from rdb$relation_fields rf left join rdb$relations r on rf.rdb$relation_name = r.rdb$relation_name and r.rdb$relation_id < 10")
+
+        cnt_chk, cnt_all = cur.fetchall()[0][:2]
+        
+        #------------------------------------------------------
+
+        result_map = {}
+        chk_sql = 'select 1 from sp_get_relations r join rdb$relation_fields f on f.rdb$relation_name = r.rdb$relation_name where r.rdb$relation_id < 10'
+        with cur.prepare(chk_sql) as ps:
+            cur.execute(chk_sql)
+            tabstat1 = [ p for p in con.info.get_table_access_stats() if p.table_id == rf_rel_id ]
+            cur.fetchall()
+            tabstat2 = [ p for p in con.info.get_table_access_stats() if p.table_id == rf_rel_id ]
+            print( '\n'.join([replace_leading(s) for s in ps.detailed_plan.split('\n')]) ) # explained plan, with preserving indents by replacing leading spaces with '#'
+
+        idx_reads = (tabstat2[0].indexed if tabstat2[0].indexed else 0)
+        if tabstat1:
+            idx_reads -= (tabstat1[0].indexed if tabstat1[0].indexed else 0)
+
+        print('Result:')
+        if idx_reads == 0 or idx_reads > cnt_chk:
+            print(f'POOR! Number of records in rdb$relation_fields: 1) to be filtered: {cnt_chk}, 2) total: {cnt_all}. Number of indexed_reads: {idx_reads}')
+        else:
+            print('Acceptable.')
+
+    act.expected_stdout = """
+        Select Expression
+        ####-> Nested Loop Join (inner)
+        ########-> Filter
+        ############-> Procedure "SP_GET_RELATIONS" as "R" Scan
+        ########-> Filter
+        ############-> Table "RDB$RELATION_FIELDS" as "F" Access By ID
+        ################-> Bitmap
+        ####################-> Index "RDB$INDEX_4" Range Scan (full match)
+        Result:
+        Acceptable.
+    """
+    act.stdout = capsys.readouterr().out
+    assert act.clean_stdout == act.clean_expected_stdout