firebird-qa/tests/bugs/gh_8290_test.py

#coding:utf-8

"""
ID:          issue-8290
ISSUE:       https://github.com/FirebirdSQL/firebird/issues/8290
TITLE:       "Unique scan" is incorrectly reported in the explained plan for unique index and IS NULL predicate
DESCRIPTION:
    Test creates a table and checks several cases related to issue: asc/desc, computed-by and partial indices.
    For each case we ask engine to show explained plan. Every case must have 'Range Scan (full match)'.
NOTES:
    [25.10.2024] pzotov
    Confirmed problem on 6.0.0.485, 5.0.2.1519.
    Checked on 6.0.0.502-d2f4cf6, 5.0.2.1542-ab50e20 (intermediate builds).
"""

import pytest
from firebird.qa import *

init_sql = """
    recreate table test(id int generated by default as identity, x int, y int, z int);
    insert into test(x, y, z) select null, null, null from rdb$types, rdb$types rows 1000;
    commit;
    create unique index test_x_asc on test(x);
    create unique descending index test_y_desc on test(y);
    create unique index test_x_plus_y on test computed by (x+y);

    create unique index test_z_partial on test(z) where mod(id,2) = 0;
    create unique index test_x_minus_y_partial on test computed by (x-y) where mod(id,3) <= 1;
    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('>=5.0.2')
def test_1(act: Action, capsys):

    qry_map = {
         0 : 'select count(*) from test where x is null'
        ,1 : 'select count(*) from test where y is null'
        ,2 : 'select count(*) from test where x+y is null'
        ,3 : 'select count(*) from test where z is null and mod(id,2) = 0'
        ,4 : 'select count(*) from test where x-y is null and mod(id,3) <= 1'
        ,5 : 'select count(*) from test where x is not distinct from null'
        ,6 : 'select count(*) from test where y is not distinct from null'
        ,7 : 'select count(*) from test where x+y is not distinct from null'
        ,8 : 'select count(*) from test where z is not distinct from null and mod(id,2) = 0'
        ,9 : 'select count(*) from test where x-y is not distinct from null and mod(id,3) <= 1'
    }

    with act.db.connect() as con:
        cur = con.cursor()
        for k,v in qry_map.items():
            ps = cur.prepare(v)
            # Print explained plan with padding eash line by dots in order to see indentations:
            print(v)
            print( '\n'.join([replace_leading(s) for s in ps.detailed_plan.split('\n')]) )
            print('')

            # 26.10.2024. ::: ACHTUNG :::
            # MANDATORY OTHERWISE PYTEST WILL HANG AT FINAL POINT:
            ps.free()

            
    expected_out = f"""
        {qry_map[0]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_X_ASC" Range Scan (full match)

        {qry_map[1]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_Y_DESC" Range Scan (full match)

        {qry_map[2]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_X_PLUS_Y" Range Scan (full match)

        {qry_map[3]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_Z_PARTIAL" Range Scan (full match)

        {qry_map[4]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_X_MINUS_Y_PARTIAL" Range Scan (full match)

        {qry_map[5]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_X_ASC" Range Scan (full match)

        {qry_map[6]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_Y_DESC" Range Scan (full match)

        {qry_map[7]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_X_PLUS_Y" Range Scan (full match)

        {qry_map[8]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_Z_PARTIAL" Range Scan (full match)

        {qry_map[9]}
        Select Expression
        ....-> Aggregate
        ........-> Filter
        ............-> Table "TEST" Access By ID
        ................-> Bitmap
        ....................-> Index "TEST_X_MINUS_Y_PARTIAL" Range Scan (full match)
    """

    act.expected_stdout = expected_out

    act.stdout = capsys.readouterr().out
    assert act.clean_stdout == act.clean_expected_stdout