github.com/dolthub/go-mysql-server@v0.18.0/sql/rowexec/project_test.go (about)

     1  // Copyright 2020-2021 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package rowexec
    16  
    17  import (
    18  	"io"
    19  	"testing"
    20  
    21  	"github.com/stretchr/testify/require"
    22  
    23  	"github.com/dolthub/go-mysql-server/memory"
    24  	"github.com/dolthub/go-mysql-server/sql"
    25  	"github.com/dolthub/go-mysql-server/sql/expression"
    26  	"github.com/dolthub/go-mysql-server/sql/plan"
    27  	"github.com/dolthub/go-mysql-server/sql/types"
    28  )
    29  
    30  func TestProject(t *testing.T) {
    31  	require := require.New(t)
    32  
    33  	childSchema := sql.NewPrimaryKeySchema(sql.Schema{
    34  		{Name: "col1", Type: types.Text, Nullable: true},
    35  		{Name: "col2", Type: types.Text, Nullable: true},
    36  	})
    37  
    38  	db := memory.NewDatabase("test")
    39  	pro := memory.NewDBProvider(db)
    40  	ctx := newContext(pro)
    41  
    42  	child := memory.NewTable(db.BaseDatabase, "test", childSchema, nil)
    43  	child.Insert(ctx, sql.NewRow("col1_1", "col2_1"))
    44  	child.Insert(ctx, sql.NewRow("col1_2", "col2_2"))
    45  	p := plan.NewProject(
    46  		[]sql.Expression{expression.NewGetField(1, types.Text, "col2", true)},
    47  		plan.NewResolvedTable(child, nil, nil),
    48  	)
    49  	require.Equal(1, len(p.Children()))
    50  	schema := sql.NewPrimaryKeySchema(sql.Schema{
    51  		{Name: "col2", Type: types.Text, Nullable: true},
    52  	})
    53  	require.Equal(schema.Schema, p.Schema())
    54  	iter, err := DefaultBuilder.Build(ctx, p, nil)
    55  	require.NoError(err)
    56  	require.NotNil(iter)
    57  	row, err := iter.Next(ctx)
    58  	require.NoError(err)
    59  	require.NotNil(row)
    60  	require.Equal(1, len(row))
    61  	require.Equal("col2_1", row[0])
    62  	row, err = iter.Next(ctx)
    63  	require.NoError(err)
    64  	require.NotNil(row)
    65  	require.Equal(1, len(row))
    66  	require.Equal("col2_2", row[0])
    67  	row, err = iter.Next(ctx)
    68  	require.Equal(io.EOF, err)
    69  	require.Nil(row)
    70  
    71  	p = plan.NewProject(nil, plan.NewResolvedTable(child, nil, nil))
    72  	require.Equal(0, len(p.Schema()))
    73  
    74  	p = plan.NewProject([]sql.Expression{
    75  		expression.NewAlias("foo", expression.NewGetField(1, types.Text, "col2", true)),
    76  	}, plan.NewResolvedTable(child, nil, nil))
    77  	schema = sql.NewPrimaryKeySchema(sql.Schema{
    78  		{Name: "foo", Type: types.Text, Nullable: true},
    79  	})
    80  	require.Equal(schema.Schema, p.Schema())
    81  }
    82  
    83  func BenchmarkProject(b *testing.B) {
    84  	require := require.New(b)
    85  	ctx := sql.NewEmptyContext()
    86  
    87  	for i := 0; i < b.N; i++ {
    88  		d := plan.NewProject([]sql.Expression{
    89  			expression.NewGetField(0, types.Text, "strfield", true),
    90  			expression.NewGetField(1, types.Float64, "floatfield", true),
    91  			expression.NewGetField(2, types.Boolean, "boolfield", false),
    92  			expression.NewGetField(3, types.Int32, "intfield", false),
    93  			expression.NewGetField(4, types.Int64, "bigintfield", false),
    94  			expression.NewGetField(5, types.Blob, "blobfield", false),
    95  		}, plan.NewResolvedTable(benchtable, nil, nil))
    96  
    97  		iter, err := DefaultBuilder.Build(ctx, d, nil)
    98  		require.NoError(err)
    99  		require.NotNil(iter)
   100  
   101  		for {
   102  			_, err := iter.Next(ctx)
   103  			if err == io.EOF {
   104  				break
   105  			}
   106  
   107  			require.NoError(err)
   108  		}
   109  	}
   110  }