Added/Updated tests\bugs\gh_7863_test.py: Checked on 6.0.0.223, 5.0.1.1322.

Author: pavel-zotov

tests/bugs/gh_7863_test.py

@@ -0,0 +1,97 @@
+#coding:utf-8
+
+"""
+ID:          issue-7863
+ISSUE:       7863
+TITLE:       Non-correlated sub-query is evaluated multiple times if it is based on a VIEW rathe than on appropriate derived table.
+DESCRIPTION:
+NOTES:
+    Confirmed bug on 6.0.0.222
+    Checked on 6.0.0.223, 5.0.1.1322.
+"""
+
+import pytest
+from pathlib import Path
+from firebird.qa import *
+
+init_sql = """
+    create view v_test_nr as select 1 i from rdb$fields rows 50;
+    create view v_test_ir1 as select 1 i from rdb$fields where rdb$field_name > '' rows 50;
+    create view v_test_ir2 as select 1 i from rdb$fields where rdb$field_name > '' order by rdb$field_name rows 50;
+     
+    create table test(id int);
+    insert into test(id) select row_number()over() from rdb$types rows 100;
+    commit;
+"""
+db = db_factory(init = init_sql)
+
+act = python_act('db')
+
+@pytest.mark.version('>=5.0.1')
+def test_1(act: Action, capsys):
+
+    t_map = { 'rdb$fields' : -1, }
+
+    query1 = """
+        select /* case-2 */ count(*) as cnt_via_view from test where (select i from v_test_nr rows 1) >= 0;
+    """
+
+    query2 = """
+        select /* case-3b */ count(*) as cnt_via_view from test where (select i from v_test_ir2 rows 1) >= 0;
+    """
+
+    query3 = """
+        select /* case-3a */ count(*) as cnt_via_view from test where (select i from v_test_ir1 rows 1) >= 0;
+    """
+    q_map = {query1 : '', query2 : '', query3 : ''}
+    
+    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)
+
+        for k,v in result_map.items():
+            print(k[0]) # query
+            print(f'seq={v[0]}, idx={v[1]}')
+            print('')
+
+    act.expected_stdout = f"""
+        {query1}
+        seq=1, idx=0
+
+        {query2}
+        seq=0, idx=1
+
+        {query3}
+        seq=0, idx=1
+    """
+    act.stdout = capsys.readouterr().out
+    assert act.clean_stdout == act.clean_expected_stdout