#coding:utf-8

"""
ID:          issue-4458
ISSUE:       4458
TITLE:       Error when processing an empty data set by window function, if reading indexed
DESCRIPTION:
JIRA:        CORE-4131
FBTEST:      bugs.core_4131
NOTES:
    3.0.0.30472:
    cursor identified in the UPDATE or DELETE statement is not positioned on a row. no current record for fetch operation

    [29.07.2023] pzotov
    Enclose query in execute block so that no output will be if it completes successfully.
    Previous version of test issued execution plan which had no relation to test purpose and could be changed (thus caused test to be failed).
"""

import pytest
from firebird.qa import *

db = db_factory()

test_script = """
    recreate table test(x char(31) character set unicode_fss unique using index test_x);
    commit;
    insert into test values('qwerty');
    commit;

    set term ^;
    execute block as
        declare rn int;
        declare x type of column test.x;
    begin
        select row_number() over(order by x) as rn, x
        from test
        where x = 'qwerty'
        into rn, x;
    end ^
    set term ;^

"""

act = isql_act('db', test_script)

expected_stdout = ""

@pytest.mark.version('>=3.0')
def test_1(act: Action):
    act.expected_stdout = expected_stdout
    act.execute(combine_output = True)
    assert act.clean_stdout == act.clean_expected_stdout