#!/usr/bin/env pytest
# -*- coding: utf-8 -*-
###############################################################################
# $Id: ogr_sql_test.py f4c5ca7b31bb24a35776c77e33f0e7fc30a5e7f5 2019-06-29 23:31:46 +0200 Even Rouault $
#
# Project:  GDAL/OGR Test Suite
# Purpose:  Test various OGR SQL support options.
# Author:   Frank Warmerdam <warmerdam@pobox.com>
#
###############################################################################
# Copyright (c) 2003, Frank Warmerdam <warmerdam@pobox.com>
# Copyright (c) 2008-2013, Even Rouault <even dot rouault at mines-paris dot org>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Library General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Library General Public License for more details.
#
# You should have received a copy of the GNU Library General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.
###############################################################################

import sys


from osgeo import gdal
from osgeo import ogr
import gdaltest
import ogrtest
import pytest

###############################################################################
# Test a simple query with a where clause.


def test_ogr_sql_1():
    gdaltest.ds = ogr.Open('data')
    gdaltest.lyr = gdaltest.ds.GetLayerByName('poly')

    gdaltest.lyr.SetAttributeFilter('eas_id < 167')

    count = gdaltest.lyr.GetFeatureCount()
    assert count == 3, \
        ('Got wrong count with GetFeatureCount() - %d, expecting 3' % count)

    gdaltest.lyr.SetAttributeFilter('')
    count = gdaltest.lyr.GetFeatureCount()
    assert count == 10, \
        ('Got wrong count with GetFeatureCount() - %d, expecting 10' % count)

###############################################################################
# Test DISTINCT handling


def test_ogr_sql_2():

    expect = [168, 169, 166, 158, 165]

    sql_lyr = gdaltest.ds.ExecuteSQL('select distinct eas_id from poly where eas_id < 170')

    tr = ogrtest.check_features_against_list(sql_lyr, 'eas_id', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Test ORDER BY handling


def test_ogr_sql_3():

    expect = [158, 165, 166, 168, 169]

    sql_lyr = gdaltest.ds.ExecuteSQL('select distinct eas_id from poly where eas_id < 170 order by eas_id')

    tr = ogrtest.check_features_against_list(sql_lyr, 'eas_id', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Test ORDER BY DESC handling


def test_ogr_sql_3_desc():

    expect = [169, 168, 166, 165, 158]

    sql_lyr = gdaltest.ds.ExecuteSQL('select distinct eas_id from poly where eas_id < 170 order by eas_id desc')

    tr = ogrtest.check_features_against_list(sql_lyr, 'eas_id', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Test DISTINCT and ORDER BY on strings.


def test_ogr_sql_4():

    expect = ['_158_', '_165_', '_166_', '_168_', '_170_', '_171_', '_179_']

    sql_lyr = gdaltest.ds.ExecuteSQL('select distinct name from idlink order by name asc')

    tr = ogrtest.check_features_against_list(sql_lyr, 'name', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Test column functions.


def test_ogr_sql_5():

    sql_lyr = gdaltest.ds.ExecuteSQL('select max(eas_id), min(eas_id), avg(eas_id), sum(eas_id), count(eas_id) from idlink')
    feat = sql_lyr.GetNextFeature()
    if feat['max_eas_id'] != 179:
        feat.DumpReadable()
        pytest.fail()
    if feat['min_eas_id'] != 158:
        feat.DumpReadable()
        pytest.fail()
    if abs(feat['avg_eas_id'] - 168.142857142857) > 1e-12:
        feat.DumpReadable()
        pytest.fail()
    if feat['count_eas_id'] != 7:
        feat.DumpReadable()
        pytest.fail()
    if feat['sum_eas_id'] != 1177:
        feat.DumpReadable()
        pytest.fail()
    gdaltest.ds.ReleaseResultSet(sql_lyr)

###############################################################################
# Test simple COUNT() function.


def test_ogr_sql_6():

    expect = [10]

    sql_lyr = gdaltest.ds.ExecuteSQL('select count(*) from poly')

    tr = ogrtest.check_features_against_list(sql_lyr, 'count_*', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Verify that selecting the FID works properly.


def test_ogr_sql_7():

    expect = [7, 8]

    sql_lyr = gdaltest.ds.ExecuteSQL('select eas_id, fid from poly where eas_id in (158,165)')

    tr = ogrtest.check_features_against_list(sql_lyr, 'fid', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Verify that wildcard expansion works properly.


def test_ogr_sql_8():

    expect = ['35043369', '35043408']

    sql_lyr = gdaltest.ds.ExecuteSQL('select * from poly where eas_id in (158,165)')

    tr = ogrtest.check_features_against_list(sql_lyr, 'PRFEDEA', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Verify that quoted table names work.


def test_ogr_sql_9():

    expect = ['35043369', '35043408']

    sql_lyr = gdaltest.ds.ExecuteSQL('select * from "poly" where eas_id in (158,165)')

    tr = ogrtest.check_features_against_list(sql_lyr, 'PRFEDEA', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Test the ILIKE operator.


def test_ogr_sql_10():

    expect = [170]

    sql_lyr = gdaltest.ds.ExecuteSQL("select eas_id from poly where prfedea ilike '%413'")

    tr = ogrtest.check_features_against_list(sql_lyr, 'eas_id', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Test MAX() on empty dataset.


def test_ogr_sql_11():

    expect = [None]

    sql_lyr = gdaltest.ds.ExecuteSQL("select max(eas_id) from empty")

    tr = ogrtest.check_features_against_list(sql_lyr, 'max_eas_id', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Test DISTINCT on empty dataset.


def test_ogr_sql_12():

    expect = []

    sql_lyr = gdaltest.ds.ExecuteSQL("select distinct eas_id from empty")

    tr = ogrtest.check_features_against_list(sql_lyr, 'eas_id', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Verify selection of, and on ogr_geometry.


def test_ogr_sql_13():

    expect = ['POLYGON', 'POLYGON', 'POLYGON', 'POLYGON', 'POLYGON',
              'POLYGON', 'POLYGON', 'POLYGON', 'POLYGON', 'POLYGON']

    sql_lyr = gdaltest.ds.ExecuteSQL("select ogr_geometry from poly where ogr_geometry = 'POLYGON'")

    tr = ogrtest.check_features_against_list(sql_lyr, 'ogr_geometry', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################
# Verify selection of, and on ogr_style and ogr_geom_wkt.


def test_ogr_sql_14():

    expect = [
        'BRUSH(fc:#000000,bc:#ffffff,id:"mapinfo-brush-1,ogr-brush-1");PEN(w:1px,c:#000000,id:"mapinfo-pen-2,ogr-pen-0")',
        'BRUSH(fc:#000000,bc:#ffffff,id:"mapinfo-brush-1,ogr-brush-1");PEN(w:1px,c:#000000,id:"mapinfo-pen-2,ogr-pen-0")']

    ds = ogr.Open('data/small.mif')
    sql_lyr = ds.ExecuteSQL("select ogr_style from small where ogr_geom_wkt LIKE 'POLYGON%'")

    tr = ogrtest.check_features_against_list(sql_lyr, 'ogr_style', expect)

    ds.ReleaseResultSet(sql_lyr)
    ds = None

    assert tr

###############################################################################
# Verify that selecting with filtering by FID works properly.


def test_ogr_sql_15():

    expect = [7]

    sql_lyr = gdaltest.ds.ExecuteSQL('select fid,eas_id,prfedea from poly where fid = %d' % expect[0])

    tr = ogrtest.check_features_against_list(sql_lyr, 'fid', expect)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert tr

###############################################################################


def test_ogr_sql_16():

    expect = [2]

    ds = ogr.Open('data/small.mif')
    sql_lyr = ds.ExecuteSQL("select fid from small where owner < 'H'")

    tr = ogrtest.check_features_against_list(sql_lyr, 'fid', expect)

    ds.ReleaseResultSet(sql_lyr)
    ds = None

    assert tr


###############################################################################
# Test the RFC 21 CAST operator.
#
def test_ogr_sql_17():

    expect = ['1', '2']

    ds = ogr.Open('data/small.mif')
    sql_lyr = ds.ExecuteSQL("select CAST(fid as CHARACTER(10)), CAST(data as numeric(7,3)) from small")

    fld_def = sql_lyr.GetLayerDefn().GetFieldDefn(0)

    assert fld_def.GetName() == 'fid', 'got wrong fid field name'

    if fld_def.GetType() != ogr.OFTString:
        gdaltest.post_reason('got wrong fid field type')
        print(fld_def.GetType())

    if fld_def.GetWidth() != 10:
        gdaltest.post_reason('got wrong fid field width')
        print(fld_def.GetWidth())

    fld_def = sql_lyr.GetLayerDefn().GetFieldDefn(1)

    assert fld_def.GetName() == 'data', 'got wrong data field name'

    if fld_def.GetType() != ogr.OFTReal:
        gdaltest.post_reason('got wrong data field type')
        print(fld_def.GetType())

    if fld_def.GetWidth() != 7:
        gdaltest.post_reason('got wrong data field width')
        print(fld_def.GetWidth())

    if fld_def.GetPrecision() != 3:
        gdaltest.post_reason('got wrong data field precision')
        print(fld_def.GetPrecision())

    tr = ogrtest.check_features_against_list(sql_lyr, 'fid', expect)

    ds.ReleaseResultSet(sql_lyr)
    ds = None

    assert tr


###############################################################################
# Test extended character set

def test_ogr_sql_18():

    if sys.version_info >= (3, 0, 0):
        pytest.skip()

    name = 'data/departs.vrt'

    ds = ogr.Open(name)
    assert ds is not None

    sql = 'select * from D\303\251parts'
    sql_lyr = ds.ExecuteSQL(sql)
    if sql_lyr is None:
        ds = None
        pytest.fail()
    feat = sql_lyr.GetNextFeature()
    assert feat is not None
    feat = None

    ds.ReleaseResultSet(sql_lyr)

    # Test #2221
    sql = 'select NOMd\303\251PART from D\303\251parts'
    sql_lyr = ds.ExecuteSQL(sql)
    if sql_lyr is None:
        ds = None
        pytest.fail()
    feat = sql_lyr.GetNextFeature()
    assert feat is not None
    feat = None

    ds.ReleaseResultSet(sql_lyr)
    ds = None

###############################################################################
# Test empty request string


def test_ogr_sql_19():

    gdal.PushErrorHandler('CPLQuietErrorHandler')
    sql_lyr = gdaltest.ds.ExecuteSQL('')
    gdal.PopErrorHandler()

    assert sql_lyr is None

###############################################################################
# Test query "SELECT * from my_layer" on layer without any field (#2788)


def test_ogr_sql_20():

    mem_ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    mem_lyr = mem_ds.CreateLayer("my_layer")

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    feat.SetGeometry(ogr.CreateGeometryFromWkt("POINT(0 1)"))
    mem_lyr.CreateFeature(feat)

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    feat.SetGeometry(ogr.CreateGeometryFromWkt("POINT(2 3)"))
    mem_lyr.CreateFeature(feat)

    sql_lyr = mem_ds.ExecuteSQL("SELECT * from my_layer")
    assert sql_lyr.GetFeatureCount() == 2
    mem_ds.ReleaseResultSet(sql_lyr)
    mem_ds = None

###############################################################################
# Test query "SELECT *, fid from my_layer" on layer without any field (#2788)


def test_ogr_sql_21():

    mem_ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    mem_ds.CreateLayer("my_layer")

    sql_lyr = mem_ds.ExecuteSQL("SELECT *, fid from my_layer")
    assert sql_lyr.GetLayerDefn().GetFieldCount() == 1
    assert sql_lyr.GetLayerDefn().GetFieldDefn(0).GetName() == 'fid'
    mem_ds.ReleaseResultSet(sql_lyr)
    mem_ds = None

###############################################################################
# Test multiple expansion of '*' as in "SELECT *, fid, *, my_layer.* from my_layer" (#2788)


def test_ogr_sql_22():

    mem_ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    mem_lyr = mem_ds.CreateLayer("my_layer")
    mem_lyr.CreateField(ogr.FieldDefn("test", ogr.OFTString))

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    feat.SetGeometry(ogr.CreateGeometryFromWkt("POINT(0 1)"))
    mem_lyr.CreateFeature(feat)

    sql_lyr = mem_ds.ExecuteSQL("SELECT *, fid, *, my_layer.* from my_layer")
    assert sql_lyr.GetLayerDefn().GetFieldCount() == 4
    assert sql_lyr.GetLayerDefn().GetFieldDefn(0).GetName() == 'test'
    assert sql_lyr.GetLayerDefn().GetFieldDefn(1).GetName() == 'fid'
    assert sql_lyr.GetLayerDefn().GetFieldDefn(2).GetName() == 'test'
    assert sql_lyr.GetLayerDefn().GetFieldDefn(3).GetName() == 'my_layer.test'
    mem_ds.ReleaseResultSet(sql_lyr)
    mem_ds = None

###############################################################################
# Test query "SELECT DISTINCT test from my_layer" (#2788)


def test_ogr_sql_23():

    mem_ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    mem_lyr = mem_ds.CreateLayer("my_layer")
    mem_lyr.CreateField(ogr.FieldDefn("test", ogr.OFTString))

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    feat.SetField("test", 0)
    feat.SetGeometry(ogr.CreateGeometryFromWkt("POINT(0 1)"))
    mem_lyr.CreateFeature(feat)

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    feat.SetField("test", 1)
    feat.SetGeometry(ogr.CreateGeometryFromWkt("POINT(2 3)"))
    mem_lyr.CreateFeature(feat)

    sql_lyr = mem_ds.ExecuteSQL("SELECT DISTINCT test from my_layer")
    assert sql_lyr.GetFeatureCount() == 2
    mem_ds.ReleaseResultSet(sql_lyr)
    mem_ds = None

###############################################################################
# Test that style strings get carried with OGR SQL SELECT results. (#2808)


def test_ogr_sql_24():

    result = 'success'

    ds = ogr.Open('data/smalltest.dgn')

    sql_layer = ds.ExecuteSQL('SELECT * from elements where colorindex=83 and type=3')

    feat = sql_layer.GetNextFeature()
    if len(feat.GetStyleString()) < 10:
        print(feat.GetStyleString())
        gdaltest.post_reason('style string apparently not propagated to OGR SQL results.')
        result = 'fail'
    feat = None
    ds.ReleaseResultSet(sql_layer)
    ds = None

    return result

###############################################################################
# Test for OGR_GEOM_AREA special field (#2949)


def test_ogr_sql_25():

    mem_ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    mem_lyr = mem_ds.CreateLayer("my_layer")
    mem_lyr.CreateField(ogr.FieldDefn("test", ogr.OFTString))

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    feat.SetField("test", 0)
    feat.SetGeometry(ogr.CreateGeometryFromWkt("POLYGON((0 0,0 1,1 1,1 0,0 0))"))
    mem_lyr.CreateFeature(feat)

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    feat.SetField("test", 1)
    feat.SetGeometry(ogr.CreateGeometryFromWkt("POLYGON((0 0,0 0.5,0.5 0.5,0.5 0,0 0))"))
    mem_lyr.CreateFeature(feat)

    sql_lyr = mem_ds.ExecuteSQL("SELECT test, OGR_GEOM_AREA from my_layer WHERE OGR_GEOM_AREA > 0.9")
    assert sql_lyr.GetFeatureCount() == 1
    feat = sql_lyr.GetNextFeature()
    assert feat.GetFieldAsDouble('OGR_GEOM_AREA') == 1.0
    assert feat.GetFieldAsString('test') == '0'
    mem_ds.ReleaseResultSet(sql_lyr)

    mem_ds = None

###############################################################################
# Test query 'SELECT 'literal_value' AS column_name FROM a_table'
#


def test_ogr_sql_26():

    mem_ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    mem_lyr = mem_ds.CreateLayer("my_layer")

    feat = ogr.Feature(mem_lyr.GetLayerDefn())
    mem_lyr.CreateFeature(feat)

    sql_lyr = mem_ds.ExecuteSQL("SELECT 'literal_value' AS my_column, 'literal_value2' my_column2 FROM my_layer")
    assert sql_lyr.GetFeatureCount() == 1
    feat = sql_lyr.GetNextFeature()
    assert feat.GetFieldAsString('my_column') == 'literal_value'
    assert feat.GetFieldAsString('my_column2') == 'literal_value2'
    mem_ds.ReleaseResultSet(sql_lyr)

    mem_ds = None

###############################################################################

###############################################################################
# Test query on datetime columns
#


def test_ogr_sql_27():

    ds = ogr.Open('data/testdatetime.csv')

    sql_lyr = ds.ExecuteSQL("SELECT * FROM testdatetime WHERE "
                            "timestamp < '2010/04/01 00:00:00' AND "
                            "timestamp > '2009/11/15 11:59:59' AND "
                            "timestamp != '2009/12/31 23:00:00' "
                            "ORDER BY timestamp DESC")

    tr = ogrtest.check_features_against_list(sql_lyr, 'name', ['foo5', 'foo4'])

    ds.ReleaseResultSet(sql_lyr)
    ds = None

    assert tr


###############################################################################
# Test robustness against invalid SQL statements.
# With RFC 28 new implementation, most of them are directly caught by the generated
# code from the grammar

def test_ogr_sql_28():

    ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    lyr = ds.CreateLayer("my_layer")
    lyr.GetLayerDefn().GetGeomFieldDefn(0).SetName('geom')  # a bit border line but OK for Memory driver...
    field_defn = ogr.FieldDefn("strfield", ogr.OFTString)
    lyr.CreateField(field_defn)
    field_defn = ogr.FieldDefn("intfield", ogr.OFTInteger)
    lyr.CreateField(field_defn)

    lyr = ds.CreateLayer("my_layer2")
    field_defn = ogr.FieldDefn("strfield", ogr.OFTString)
    lyr.CreateField(field_defn)
    field_defn = ogr.FieldDefn("strfield2", ogr.OFTString)
    lyr.CreateField(field_defn)

    with pytest.raises(Exception):
        sql_lyr = ds.ExecuteSQL(None)
        pytest.fail('expected exception on NULL query')

    queries = [
        '',
        '1',
        '*',
        'SELECT',
        "SELECT ' FROM my_layer",
        'SELECT + FROM my_layer',
        'SELECT (1 FROM my_layer',
        'SELECT (1)) FROM my_layer',
        'SELECT (1,) FROM my_layer',
        'SELECT 1 + FROM my_layer',
        "SELECT 1 + 'a' FROM my_layer",
        'SELECT 1 - FROM my_layer',
        'SELECT 1 * FROM my_layer',
        'SELECT 1 % FROM my_layer',
        'SELECT *',
        'SELECT * FROM',
        'SELECT * FROM foo',
        'SELECT FROM my_layer',
        'SELECT FROM FROM my_layer',
        "SELECT ('strfield'",
        "SELECT 'strfield' +",
        "SELECT 'strfield' 'strfield'",
        "SELECT CONCAT('strfield')",
        'SELECT foo(strfield) FROM my_layer',  # Undefined function 'foo' used.
        'SELECT strfield, FROM my_layer',
        'SELECT strfield, foo FROM my_layer',
        'SELECT strfield AS FROM my_layer',
        'SELECT strfield AS 1 FROM my_layer',
        'SELECT strfield AS strfield2 FROM',
        'SELECT strfield + intfield FROM my_layer',
        'SELECT CAST',
        'SELECT CAST(',
        'SELECT CAST(strfield',
        'SELECT CAST(strfield AS',
        'SELECT CAST(strfield AS foo',
        'SELECT CAST(strfield AS foo)',
        'SELECT CAST(strfield AS foo) FROM',
        'SELECT CAST(strfield AS foo) FROM my_layer',
        'SELECT CAST(strfield AS CHARACTER',
        'SELECT CAST(strfield AS CHARACTER)',
        'SELECT CAST(strfield AS CHARACTER) FROM',
        'SELECT CAST(strfield AS CHARACTER) FROM foo',
        'SELECT CAST(strfield AS CHARACTER(',
        'SELECT CAST(strfield AS CHARACTER(2',
        'SELECT CAST(strfield AS CHARACTER(2)',
        'SELECT CAST(strfield AS CHARACTER(2))',
        'SELECT CAST(strfield AS CHARACTER(2)) FROM',
        'SELECT CAST(strfield AS CHARACTER(2)) FROM foo',
        'SELECT CAST(strfield AS 1) FROM my_layer',
        'SELECT * FROM my_layer WHERE',
        # 'SELECT * FROM my_layer WHERE strfield',
        'SELECT * FROM my_layer WHERE strfield = ',
        'SELECT * FROM my_layer WHERE strfield = foo',
        "SELECT * FROM my_layer WHERE foo = 'a'",
        "SELECT * FROM my_layer WHERE strfield = 'a"
        "SELECT * FROM my_layer WHERE strfield = 'a' ORDER ",
        "SELECT * FROM my_layer WHERE strfield = 'a' ORDER BY",
        "SELECT * FROM my_layer WHERE strfield = 'a' ORDER BY foo",
        "SELECT * FROM my_layer WHERE strfield = 'a' ORDER BY strfield UNK",
        "SELECT * FROM my_layer ORDER BY geom",  # Cannot use geometry field 'geom' in a ORDER BY clause
        "SELECT FOO(*) FROM my_layer",
        "SELECT FOO(*) AS bar FROM my_layer",
        "SELECT COUNT",
        "SELECT COUNT(",
        "SELECT COUNT() FROM my_layer",
        "SELECT COUNT(*",
        "SELECT COUNT(*)",
        "SELECT COUNT(*) FROM",
        "SELECT COUNT(*) AS foo FROM",
        "SELECT COUNT(* FROM my_layer",
        "SELECT COUNT(FOO intfield) FROM my_layer",
        "SELECT COUNT(DISTINCT intfield FROM my_layer",
        "SELECT COUNT(DISTINCT *) FROM my_layer",
        "SELECT FOO(DISTINCT intfield) FROM my_layer",
        "SELECT FOO(DISTINCT intfield) as foo FROM my_layer",
        "SELECT DISTINCT foo FROM my_layer",
        "SELECT DISTINCT foo AS 'id' 'id2' FROM",
        "SELECT DISTINCT foo AS id id2 FROM",
        "SELECT DISTINCT FROM my_layer",
        "SELECT DISTINCT strfield, COUNT(DISTINCT intfield) FROM my_layer",
        "SELECT MIN(intfield*2) FROM my_layer",
        "SELECT MIN(intfield,2) FROM my_layer",
        "SELECT MIN(foo) FROM my_layer",
        "SELECT MAX(foo) FROM my_layer",
        "SELECT SUM(foo) FROM my_layer",
        "SELECT AVG(foo) FROM my_layer",
        "SELECT MIN(strfield) FROM my_layer",
        "SELECT MAX(strfield) FROM my_layer",
        "SELECT SUM(strfield) FROM my_layer",
        "SELECT AVG(strfield) FROM my_layer",
        "SELECT AVG(intfield, intfield) FROM my_layer",
        "SELECT * FROM my_layer WHERE AVG(intfield) = 1",
        "SELECT * FROM 'foo' foo",
        "SELECT * FROM my_layer WHERE strfield =",
        "SELECT * FROM my_layer WHERE strfield = foo",
        "SELECT * FROM my_layer WHERE strfield = intfield",
        "SELECT * FROM my_layer WHERE strfield = 1",
        "SELECT * FROM my_layer WHERE strfield = '1' AND",
        # "SELECT * FROM my_layer WHERE 1 AND 2" ,
        "SELECT * FROM my_layer WHERE strfield LIKE",
        "SELECT * FROM my_layer WHERE strfield LIKE 1",
        "SELECT * FROM my_layer WHERE strfield IS",
        "SELECT * FROM my_layer WHERE strfield IS NOT",
        "SELECT * FROM my_layer WHERE strfield IS foo",
        "SELECT * FROM my_layer WHERE strfield IS NOT foo",
        "SELECT * FROM my_layer WHERE (strfield IS NOT NULL",
        "SELECT * FROM my_layer WHERE strfield IN",
        "SELECT * FROM my_layer WHERE strfield IN(",
        "SELECT * FROM my_layer WHERE strfield IN()",
        "SELECT * FROM my_layer WHERE strfield IN('a'",
        "SELECT * FROM my_layer WHERE strfield IN('a',",
        "SELECT * FROM my_layer WHERE strfield IN('a','b'",
        "SELECT * FROM my_layer WHERE strfield IN('a','b'))",
        "SELECT * FROM my_layer LEFT",
        "SELECT * FROM my_layer LEFT JOIN",
        "SELECT * FROM my_layer LEFT JOIN foo",
        "SELECT * FROM my_layer LEFT JOIN foo ON my_layer.strfield = my_layer2.strfield",
        "SELECT * FROM my_layer LEFT JOIN my_layer2 ON my_layer.strfield = foo.strfield",
        "SELECT * FROM my_layer LEFT JOIN my_layer2 ON my_layer.strfield = my_layer2.foo",
        # "SELECT * FROM my_layer LEFT JOIN my_layer2 ON my_layer.strfield != my_layer2.strfield",
        "SELECT *, my_layer2. FROM my_layer LEFT JOIN my_layer2 ON my_layer.strfield = my_layer2.strfield",
        "SELECT *, my_layer2.foo FROM my_layer LEFT JOIN my_layer2 ON my_layer.strfield = my_layer2.strfield",
        "SELECT * FROM my_layer UNION",
        "SELECT * FROM my_layer UNION ALL",
        "SELECT * FROM my_layer UNION ALL SELECT",
        "SELECT * FROM my_layer UNION ALL SELECT *",
        "SELECT * FROM my_layer UNION ALL SELECT * FROM",
    ]

    for query in queries:
        gdal.ErrorReset()
        # print query
        gdal.PushErrorHandler('CPLQuietErrorHandler')
        sql_lyr = ds.ExecuteSQL(query)
        gdal.PopErrorHandler()
        if sql_lyr is not None:
            ds.ReleaseResultSet(sql_lyr)
            pytest.fail('expected None result on "%s"' % query)
        assert gdal.GetLastErrorType() != 0, ('expected error on "%s"' % query)

    ds = None

###############################################################################
# Verify that IS NULL and IS NOT NULL are working


def test_ogr_sql_29():

    ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    lyr = ds.CreateLayer("my_layer")
    field_defn = ogr.FieldDefn("strfield", ogr.OFTString)
    lyr.CreateField(field_defn)

    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(0, 'a')
    lyr.CreateFeature(feat)

    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(0, 'b')
    lyr.CreateFeature(feat)

    feat = ogr.Feature(lyr.GetLayerDefn())
    lyr.CreateFeature(feat)

    sql_lyr = ds.ExecuteSQL('select * from my_layer where strfield is null')
    count_is_null = sql_lyr.GetFeatureCount()
    ds.ReleaseResultSet(sql_lyr)

    sql_lyr = ds.ExecuteSQL('select * from my_layer where strfield is not null')
    count_is_not_null = sql_lyr.GetFeatureCount()
    ds.ReleaseResultSet(sql_lyr)

    ds = None

    assert count_is_null == 1, 'IS NULL failed'

    assert count_is_not_null == 2, 'IS NOT NULL failed'

###############################################################################
# Verify a select mixing a count(*) with something else works without errors


def test_ogr_sql_30():

    gdal.ErrorReset()

    sql_lyr = gdaltest.ds.ExecuteSQL('select min(eas_id), count(*) from poly')

    feat = sql_lyr.GetNextFeature()
    val_count = feat.GetField(1)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert gdal.GetLastErrorMsg() == ''

    assert val_count == 10

###############################################################################
# Regression test for #4022


def test_ogr_sql_31():

    gdal.ErrorReset()

    sql_lyr = gdaltest.ds.ExecuteSQL('select min(eas_id) from poly where area = 0')

    feat = sql_lyr.GetNextFeature()
    val = feat.GetField(0)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert gdal.GetLastErrorMsg() == ''

    assert val is None

###############################################################################
# Regression test for #4022 (same as above, but with dialect = 'OGRSQL')


def test_ogr_sql_32():

    gdal.ErrorReset()

    sql_lyr = gdaltest.ds.ExecuteSQL('select min(eas_id) from poly where area = 0',
                                     dialect='OGRSQL')

    feat = sql_lyr.GetNextFeature()
    val = feat.GetField(0)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert gdal.GetLastErrorMsg() == ''

    assert val is None

###############################################################################
# Check ALTER TABLE commands


def test_ogr_sql_33():

    ds = ogr.GetDriverByName("Memory").CreateDataSource("my_ds")
    lyr = ds.CreateLayer("my_layer")

    # We support with and without COLUMN keyword
    for extrakeyword in ('COLUMN ', ''):
        sql = 'ALTER TABLE my_layer ADD %smyfield NUMERIC(20, 8)' % extrakeyword
        ds.ExecuteSQL(sql)
        assert (lyr.GetLayerDefn().GetFieldIndex('myfield') != -1 and \
                lyr.GetLayerDefn().GetFieldDefn(lyr.GetLayerDefn().GetFieldIndex('myfield')).GetType() == ogr.OFTReal and \
                lyr.GetLayerDefn().GetFieldDefn(lyr.GetLayerDefn().GetFieldIndex('myfield')).GetWidth() == 20 and \
                lyr.GetLayerDefn().GetFieldDefn(lyr.GetLayerDefn().GetFieldIndex('myfield')).GetPrecision() == 8), \
            ('%s failed' % sql)

        sql = 'ALTER TABLE my_layer RENAME %smyfield TO "myfield 2"' % extrakeyword
        ds.ExecuteSQL(sql)
        assert (lyr.GetLayerDefn().GetFieldIndex('myfield') == -1 and \
                lyr.GetLayerDefn().GetFieldIndex('myfield 2') != -1), \
            ('%s failed' % sql)

        sql = 'ALTER TABLE my_layer ALTER %s"myfield 2" TYPE CHARACTER' % extrakeyword
        ds.ExecuteSQL(sql)
        assert lyr.GetLayerDefn().GetFieldDefn(lyr.GetLayerDefn().GetFieldIndex('myfield 2')).GetType() == ogr.OFTString, \
            ('%s failed' % sql)

        sql = 'ALTER TABLE my_layer ALTER %s"myfield 2" TYPE CHARACTER(15)' % extrakeyword
        ds.ExecuteSQL(sql)
        assert lyr.GetLayerDefn().GetFieldDefn(lyr.GetLayerDefn().GetFieldIndex('myfield 2')).GetWidth() == 15, \
            ('%s failed' % sql)

        sql = 'ALTER TABLE my_layer DROP %s"myfield 2"' % extrakeyword
        ds.ExecuteSQL(sql)
        assert lyr.GetLayerDefn().GetFieldIndex('myfield 2') == -1, ('%s failed' % sql)

    ds = None

###############################################################################
# Test implicit conversion from string to numeric (#4259)


def test_ogr_sql_34():

    sql_lyr = gdaltest.ds.ExecuteSQL("select count(*) from poly where eas_id in ('165')")

    feat = sql_lyr.GetNextFeature()
    val = feat.GetField(0)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert val == 1

    gdal.PushErrorHandler('CPLQuietErrorHandler')
    sql_lyr = gdaltest.ds.ExecuteSQL("select count(*) from poly where eas_id in ('a165')")
    gdal.PopErrorHandler()
    assert sql_lyr is None

###############################################################################
# Test huge SQL queries (#4262)


def test_ogr_sql_35():

    cols = "area"
    for _ in range(10):
        cols = cols + "," + cols
    sql_lyr = gdaltest.ds.ExecuteSQL("select %s from poly" % cols)

    count_cols = sql_lyr.GetLayerDefn().GetFieldCount()

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert count_cols == 1024

###############################################################################
# Test select distinct on null values (#4353)


def test_ogr_sql_36():

    ds = ogr.GetDriverByName('Memory').CreateDataSource('ogr_sql_36')
    lyr = ds.CreateLayer('layer')
    lyr.CreateField(ogr.FieldDefn('intfield', ogr.OFTInteger))
    lyr.CreateField(ogr.FieldDefn('floatfield', ogr.OFTReal))
    lyr.CreateField(ogr.FieldDefn('strfield', ogr.OFTString))
    lyr.CreateField(ogr.FieldDefn('int64field', ogr.OFTInteger64))
    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(0, 1)
    feat.SetField(1, 2.3)
    feat.SetField(2, "456")
    feat.SetField(3, 1234567890123)
    lyr.CreateFeature(feat)
    feat = ogr.Feature(lyr.GetLayerDefn())
    lyr.CreateFeature(feat)
    feat = None

    for fieldname in ['intfield', 'int64field', 'floatfield', 'strfield']:
        sql_lyr = ds.ExecuteSQL("select distinct %s from layer order by %s asc" % (fieldname, fieldname))
        feat = sql_lyr.GetNextFeature()
        if feat.IsFieldSetAndNotNull(0) != 0:
            feat.DumpReadable()
            pytest.fail('field %s' % fieldname)
        feat = sql_lyr.GetNextFeature()
        if feat.IsFieldSetAndNotNull(0) == 0:
            feat.DumpReadable()
            pytest.fail('field %s' % fieldname)
        ds.ReleaseResultSet(sql_lyr)

    for fieldname in ['intfield', 'int64field', 'floatfield', 'strfield']:
        sql_lyr = ds.ExecuteSQL("select distinct %s from layer order by %s desc" % (fieldname, fieldname))
        feat = sql_lyr.GetNextFeature()
        if feat.IsFieldSetAndNotNull(0) == 0:
            feat.DumpReadable()
            pytest.fail('field %s' % fieldname)
        feat = sql_lyr.GetNextFeature()
        if feat.IsFieldSetAndNotNull(0) != 0:
            feat.DumpReadable()
            pytest.fail('field %s' % fieldname)
        ds.ReleaseResultSet(sql_lyr)

    
###############################################################################
# Test select count([distinct] column) with null values (#4354)


def test_ogr_sql_37():

    ds = ogr.GetDriverByName('Memory').CreateDataSource('ogr_sql_37')
    lyr = ds.CreateLayer('layer')
    lyr.CreateField(ogr.FieldDefn('intfield', ogr.OFTInteger))
    lyr.CreateField(ogr.FieldDefn('floatfield', ogr.OFTReal))
    lyr.CreateField(ogr.FieldDefn('strfield', ogr.OFTString))
    lyr.CreateField(ogr.FieldDefn('strfield_first_null', ogr.OFTString))
    lyr.CreateField(ogr.FieldDefn('strfield_never_set', ogr.OFTString))
    lyr.CreateField(ogr.FieldDefn('intfield_never_set', ogr.OFTInteger))
    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(0, 1)
    feat.SetField(2, "456")
    lyr.CreateFeature(feat)
    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(0, 1)
    feat.SetField(2, "456")
    lyr.CreateFeature(feat)
    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(1, 2.3)
    feat.SetField('strfield_first_null', "foo")
    lyr.CreateFeature(feat)
    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(1, 2.3)
    lyr.CreateFeature(feat)
    feat = None

    for fieldname in ['intfield', 'floatfield', 'strfield']:
        sql_lyr = ds.ExecuteSQL("select count(%s), count(distinct %s), count(*) from layer" % (fieldname, fieldname))
        feat = sql_lyr.GetNextFeature()
        if feat.GetFieldAsInteger(0) != 2:
            feat.DumpReadable()
            pytest.fail('field %s' % fieldname)

        if feat.GetFieldAsInteger(1) != 1:
            feat.DumpReadable()
            pytest.fail('field %s' % fieldname)

        if feat.GetFieldAsInteger(2) != 4:
            feat.DumpReadable()
            pytest.fail('field %s' % fieldname)

        ds.ReleaseResultSet(sql_lyr)

    sql_lyr = ds.ExecuteSQL("select avg(intfield) from layer where intfield is null")
    feat = sql_lyr.GetNextFeature()
    if feat.IsFieldSetAndNotNull(0) != 0:
        feat.DumpReadable()
        pytest.fail()
    ds.ReleaseResultSet(sql_lyr)

    # Fix crash when first values is null (#4509)
    sql_lyr = ds.ExecuteSQL("select distinct strfield_first_null from layer")
    feat = sql_lyr.GetNextFeature()
    if feat.IsFieldSetAndNotNull('strfield_first_null'):
        feat.DumpReadable()
        pytest.fail()
    feat = sql_lyr.GetNextFeature()
    if feat.GetFieldAsString('strfield_first_null') != 'foo':
        feat.DumpReadable()
        pytest.fail()
    ds.ReleaseResultSet(sql_lyr)

    sql_lyr = ds.ExecuteSQL("select distinct strfield_never_set from layer")
    feat = sql_lyr.GetNextFeature()
    if feat.IsFieldSetAndNotNull('strfield_never_set'):
        feat.DumpReadable()
        pytest.fail()
    ds.ReleaseResultSet(sql_lyr)

    sql_lyr = ds.ExecuteSQL("select min(intfield_never_set), max(intfield_never_set), avg(intfield_never_set), sum(intfield_never_set), count(intfield_never_set) from layer")
    feat = sql_lyr.GetNextFeature()
    if feat.IsFieldSetAndNotNull(0) or feat.IsFieldSetAndNotNull(1) or feat.IsFieldSetAndNotNull(2) or feat.IsFieldSetAndNotNull(3) or feat.GetField(4) != 0:
        feat.DumpReadable()
        pytest.fail()
    ds.ReleaseResultSet(sql_lyr)

###############################################################################
# Test "SELECT MAX(OGR_GEOM_AREA) FROM XXXX" (#4633)


def test_ogr_sql_38():

    sql_lyr = gdaltest.ds.ExecuteSQL("SELECT MAX(OGR_GEOM_AREA) FROM poly")

    feat = sql_lyr.GetNextFeature()
    val = feat.GetFieldAsDouble(0)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    if abs(val - 1634833.39062) < 1e-5:
        return
    pytest.fail(val)

###############################################################################
# Test ORDER BY on a float special field


def test_ogr_sql_39():

    sql_lyr = gdaltest.ds.ExecuteSQL("SELECT * FROM poly ORDER BY OGR_GEOM_AREA")

    feat = sql_lyr.GetNextFeature()
    val = feat.GetFieldAsDouble(0)

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    if abs(val - 5268.813) < 1e-5:
        return
    pytest.fail(val)

###############################################################################
# Test ORDER BY on a int special field


def test_ogr_sql_40():

    sql_lyr = gdaltest.ds.ExecuteSQL("SELECT * FROM poly ORDER BY FID DESC")

    feat = sql_lyr.GetNextFeature()

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert feat.GetFID() == 9

###############################################################################
# Test ORDER BY on a string special field


def test_ogr_sql_41():

    sql_lyr = gdaltest.ds.ExecuteSQL("SELECT * FROM poly ORDER BY OGR_GEOMETRY")

    feat = sql_lyr.GetNextFeature()

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    assert feat.GetFID() == 0

###############################################################################
# Test comparing to empty string


def test_ogr_sql_42():

    lyr = gdaltest.ds.GetLayerByName('poly')
    lyr.SetAttributeFilter("prfedea <> ''")
    feat = lyr.GetNextFeature()
    lyr.SetAttributeFilter(None)
    assert feat is not None

    sql_lyr = gdaltest.ds.ExecuteSQL("SELECT * FROM poly WHERE prfedea <> ''")
    feat = sql_lyr.GetNextFeature()
    gdaltest.ds.ReleaseResultSet(sql_lyr)
    assert feat is not None

###############################################################################
# Test escape sequences


def test_ogr_sql_43():

    ret = 'success'
    sql = "SELECT '\"' as a, '\\\'' as b, '\'\'' as c FROM poly"
    sql_lyr = gdaltest.ds.ExecuteSQL(sql)

    feat = sql_lyr.GetNextFeature()
    if feat['a'] != '"' or feat['b'] != '\'' or feat['c'] != '\'':
        ret = 'fail'

    gdaltest.ds.ReleaseResultSet(sql_lyr)

    return ret

###############################################################################
# Test hstore_get_value()


def test_ogr_sql_44():

    # Invalid parameters
    for sql in ["SELECT hstore_get_value('a') FROM poly",
                "SELECT hstore_get_value(1, 1) FROM poly"]:
        gdal.PushErrorHandler('CPLQuietErrorHandler')
        sql_lyr = gdaltest.ds.ExecuteSQL(sql)
        gdal.PopErrorHandler()
        assert sql_lyr is None, sql

    # Invalid hstore syntax or empty result
    for sql in ["SELECT hstore_get_value('a', null) FROM poly",
                "SELECT hstore_get_value(null, 'a') FROM poly",
                "SELECT hstore_get_value('a', 'a') FROM poly",
                "SELECT hstore_get_value('a=>b', 'c') FROM poly",
                "SELECT hstore_get_value('a=>', 'a') FROM poly",
                "SELECT hstore_get_value(' a => ', 'a') FROM poly",
                "SELECT hstore_get_value('a=>b,z,c=>d', 'c') FROM poly",
                "SELECT hstore_get_value('\"a', 'a') FROM poly",
                "SELECT hstore_get_value('\"a\"', 'a') FROM poly",
                "SELECT hstore_get_value('\"a\"=', 'a') FROM poly",
                "SELECT hstore_get_value('\"a\" =>', 'a') FROM poly",
                "SELECT hstore_get_value('\"a\" => ', 'a') FROM poly",
                "SELECT hstore_get_value('\"a\" => \"', 'a') FROM poly",
                "SELECT hstore_get_value('\"a\" => \"\" z', 'a') FROM poly"]:
        sql_lyr = gdaltest.ds.ExecuteSQL(sql)
        f = sql_lyr.GetNextFeature()
        if f.IsFieldSetAndNotNull(0):
            f.DumpReadable()
            pytest.fail(sql)
        gdaltest.ds.ReleaseResultSet(sql_lyr)

    # Valid hstore syntax
    for (sql, expected) in [("SELECT hstore_get_value('a=>b', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value(' a => b ', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value('\"a\"=>b', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value(' \"a\" =>b', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value('a=>\"b\"', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value('a=> \"b\" ', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value('\"a\"=>\"b\"', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value(' \"a\" => \"b\" ', 'a') FROM poly", 'b'),
                            ("SELECT hstore_get_value(' \"a\\\"b\" => \"b\" ', 'a\"b') FROM poly", 'b')]:
        sql_lyr = gdaltest.ds.ExecuteSQL(sql)
        f = sql_lyr.GetNextFeature()
        if f.GetField(0) != expected:
            f.DumpReadable()
            pytest.fail(sql)
        gdaltest.ds.ReleaseResultSet(sql_lyr)

    
###############################################################################
# Test 64 bit GetFeatureCount()


def test_ogr_sql_45():

    ds = ogr.Open("""<OGRVRTDataSource>
  <OGRVRTLayer name="poly">
    <SrcDataSource relativeToVRT="0" shared="1">data/poly.shp</SrcDataSource>
    <SrcLayer>poly</SrcLayer>
    <GeometryType>wkbPolygon</GeometryType>
    <Field name="AREA" type="Real" src="AREA"/>
    <Field name="EAS_ID" type="Integer" src="EAS_ID"/>
    <Field name="PRFEDEA" type="Integer" src="PRFEDEA"/>
    <FeatureCount>1000000000000</FeatureCount>
  </OGRVRTLayer>
</OGRVRTDataSource>""")
    lyr = ds.GetLayer(0)

    assert lyr.GetFeatureCount() == 1000000000000

    sql_lyr = ds.ExecuteSQL('SELECT COUNT(*) FROM poly')
    f = sql_lyr.GetNextFeature()
    assert f.GetField(0) == 1000000000000
    f = None
    ds.ReleaseResultSet(sql_lyr)

    sql_lyr = ds.ExecuteSQL('SELECT COUNT(AREA) FROM poly')
    assert sql_lyr.GetLayerDefn().GetFieldDefn(0).GetType() == ogr.OFTInteger
    f = sql_lyr.GetNextFeature()
    assert f.GetField(0) == 10
    f = None
    ds.ReleaseResultSet(sql_lyr)

###############################################################################
# Test strict SQL quoting


def test_ogr_sql_46():

    ds = ogr.GetDriverByName('Memory').CreateDataSource('test')
    lyr = ds.CreateLayer('test')
    lyr.CreateField(ogr.FieldDefn('id', ogr.OFTInteger))
    lyr.CreateField(ogr.FieldDefn('from', ogr.OFTString))
    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(0, 1)
    feat.SetField(1, "not_from")
    lyr.CreateFeature(feat)
    feat = ogr.Feature(lyr.GetLayerDefn())
    feat.SetField(0, 3)
    feat.SetField(1, "from")
    lyr.CreateFeature(feat)
    feat = None

    sql_lyr = ds.ExecuteSQL("select id, 'id', \"id\" as id2, id as \"id3\", \"from\" from test where \"from\" = 'from'")
    feat = sql_lyr.GetNextFeature()
    if feat.GetField(0) != 3 or feat.GetField(1) != 'id' or feat.GetField(2) != 3 or feat.GetField(3) != 3 or feat.GetField(4) != 'from':
        feat.DumpReadable()
        pytest.fail()
    feat = sql_lyr.GetNextFeature()
    assert feat is None
    ds.ReleaseResultSet(sql_lyr)

    sql_lyr = ds.ExecuteSQL("select max(\"id\"), max(id), count(\"id\"), count(id) from \"test\"")
    feat = sql_lyr.GetNextFeature()
    if feat.GetField(0) != 3 or feat.GetField(1) != 3 or feat.GetField(2) != 2 or feat.GetField(3) != 2:
        feat.DumpReadable()
        pytest.fail()
    ds.ReleaseResultSet(sql_lyr)

    # Not accepted
    gdal.PushErrorHandler()
    sql_lyr = ds.ExecuteSQL("select * from 'test'")
    gdal.PopErrorHandler()
    assert sql_lyr is None

    # Not accepted
    gdal.PushErrorHandler()
    sql_lyr = ds.ExecuteSQL("select distinct 'id' from 'test'")
    gdal.PopErrorHandler()
    assert sql_lyr is None

    # Not accepted
    gdal.PushErrorHandler()
    sql_lyr = ds.ExecuteSQL("select max('id') from 'test'")
    gdal.PopErrorHandler()
    assert sql_lyr is None

    # Not accepted
    gdal.PushErrorHandler()
    sql_lyr = ds.ExecuteSQL("select id as 'id2' from 'test'")
    gdal.PopErrorHandler()
    assert sql_lyr is None

###############################################################################
# Test NULL sorting (#6155)


def test_ogr_sql_47():

    ds = ogr.Open('data/sort_test.dbf')
    sql_lyr = ds.ExecuteSQL('SELECT * FROM sort_test ORDER BY text_value')
    prec_val = ''
    for f in sql_lyr:
        if f.IsFieldSetAndNotNull('text_value'):
            new_val = f['text_value']
        else:
            new_val = ''
        assert new_val >= prec_val, ("new_val = '%s', prec_val = '%s'" % (new_val, prec_val))
        prec_val = new_val
    ds.ReleaseResultSet(sql_lyr)

###############################################################################
# Test sorting of more than 100 elements


def test_ogr_sql_48():

    ds = ogr.GetDriverByName('Memory').CreateDataSource('')
    lyr = ds.CreateLayer('test', geom_type=ogr.wkbNone)
    lyr.CreateField(ogr.FieldDefn('int_field', ogr.OFTInteger))
    for i in range(1000):
        f = ogr.Feature(lyr.GetLayerDefn())
        if (i % 2) == 0:
            f.SetField(0, i + 1)
        else:
            f.SetField(0, 1001 - i)
        lyr.CreateFeature(f)
    sql_lyr = ds.ExecuteSQL('SELECT * FROM test ORDER BY int_field')
    i = 1
    for f in sql_lyr:
        if f['int_field'] != i:
            f.DumpReadable()
            pytest.fail()
        i = i + 1
    ds.ReleaseResultSet(sql_lyr)
    assert i == 1001


def test_ogr_sql_cleanup():
    gdaltest.lyr = None
    gdaltest.ds = None



