Added/Updated tests\bugs\gh_7388_test.py: Checked on 6.0.0.218, 5.0.1.1318.

tests/bugs/gh_7388_test.py

@@ -0,0 +1,144 @@
+#coding:utf-8
+
+"""
+ID:          issue-7388
+ISSUE:       7388
+TITLE:       Different invariants optimization between views and CTEs
+DESCRIPTION:
+    We run two queries as described in the ticket (see variables 'query1' and 'query2').
+    For each of them we gather table statistics (sequential and indexed reads) and explained plan.
+    If any value in the pair (seq, idx) differ between two statistics then we print all info about that plus explained plans.
+    Otherwise we can consider test passed (without printing any concrete data from statistics or explained plans).
+NOTES:
+    [20.01.2024] pzotov
+    Confirmed problem on 5.0.0.871.
+    Checked on 6.0.0.218, 5.0.1.1318.
+"""
+
+import pytest
+from pathlib import Path
+from firebird.qa import *
+
+init_sql = """
+    create view v1
+    as select r.rdb$relation_id as id, r.rdb$relation_name as name
+    from rdb$relations r
+    inner join rdb$relation_fields rf on r.rdb$relation_name = rf.rdb$relation_name
+    left join rdb$security_classes sc on r.rdb$security_class = sc.rdb$security_class
+    ;
+    commit;
+"""
+db = db_factory(init = init_sql)
+
+act = python_act('db')
+
+SUCCESS_MSG = "Expected: table statistics are identical."
+
+
+#----------------------------------------------------------
+
+def replace_leading(source, char="#"):
+    stripped = source.lstrip()
+    return char * (len(source) - len(stripped)) + stripped
+
+#----------------------------------------------------------
+
+@pytest.mark.version('>=5.0')
+def test_1(act: Action, capsys):
+    t_map = { 'rdb$relation_fields' : -1, 'rdb$relations' : -1, 'rdb$security_classes' : -1 }
+
+    query1 = """
+        select 1
+        from v1
+        where id = (select max(id) from v1)
+    """
+
+    query2 = """
+        with sub as (
+        select r.rdb$relation_id as id, r.rdb$relation_name as name
+        from rdb$relations r
+          inner join rdb$relation_fields rf on r.rdb$relation_name = rf.rdb$relation_name
+          left join rdb$security_classes sc on r.rdb$security_class = sc.rdb$security_class
+        )
+        select * from sub
+        where sub.id = (select max(id) from sub)
+    """
+    q_map = {query1 : '', query2 : ''}
+    
+    with act.db.connect() as con:
+        cur = con.cursor()
+        for k in t_map.keys():
+            cur.execute(f"select rdb$relation_id from rdb$relations where rdb$relation_name = upper('{k}')")
+            test_rel_id = None
+            for r in cur:
+                test_rel_id = r[0]
+            assert test_rel_id, f"Could not find ID for relation '{k}'. Check its name!"
+            t_map[ k ] = test_rel_id
+
+        result_map = {}
+
+        for qry_txt in q_map.keys():
+            with cur.prepare(qry_txt) as ps:
+                q_map[qry_txt] = ps.detailed_plan
+                for tab_nm,tab_id in t_map.items():
+                    tabstat1 = [ p for p in con.info.get_table_access_stats() if p.table_id == tab_id ]
+                    cur.execute(qry_txt)
+                    for r in cur:
+                        pass
+                    tabstat2 = [ p for p in con.info.get_table_access_stats() if p.table_id == tab_id ]
+
+                    result_map[qry_txt, tab_nm] = \
+                        (
+                           tabstat2[0].sequential if tabstat2[0].sequential else 0
+                          ,tabstat2[0].indexed if tabstat2[0].indexed else 0
+                        )
+                    if tabstat1:
+                        seq, idx = result_map[qry_txt, tab_nm]
+                        seq -= (tabstat1[0].sequential if tabstat1[0].sequential else 0)
+                        idx -= (tabstat1[0].indexed if tabstat1[0].indexed else 0)
+                        result_map[qry_txt, tab_nm] = (seq, idx)
+
+        '''
+        print('q_map.items():')
+        for k,v in q_map.items():
+            print('k=',k)
+            print('v=',v)
+            print('')
+
+        print('')
+        print('result_map.items():')
+        for k,v in result_map.items():
+            print('(query,tab_nm)=',k)
+            print('v=',v)
+            print('')
+        '''
+
+        mism_found = 0
+        for tab_nm in t_map.keys():
+            if result_map[query1, tab_nm] == result_map[query2, tab_nm]:
+                pass
+            else:
+                print(f"Mismatch detected in the statistics for table '{tab_nm}'.")
+                print('Query-1:')
+                print('(seq,idx) =',result_map[query1, tab_nm])
+                print('Query-2:')
+                print('(seq,idx) =',result_map[query2, tab_nm])
+                mism_found += 1
+
+        if mism_found:
+            print('Check execution plans:')
+            for i,qry_txt in enumerate(q_map.keys()):
+                print('-' * 22)
+                print(f'Query-{i+1}:')
+                print(qry_txt)
+                print('-' * 22)
+                print('Plan:')
+                print( '\n'.join([replace_leading(s) for s in q_map[qry_txt].split('\n')]) ) # explained plan, with preserving indents by replacing leading spaces with '#'
+                print('')
+        else:
+            print(SUCCESS_MSG)
+
+
+    act.expected_stdout = SUCCESS_MSG
+    act.stdout = capsys.readouterr().out
+    assert act.clean_stdout == act.clean_expected_stdout