A data table that represents object graphs.
- Sort by multiple columns
- Filter by multiple columns and/or formulas that can include function calls
- Select multiple columns and/or formulas that can include scalar function calls
- Aggregate multiple columns and/or formulas that can include aggregation function calls
- Group by multiple columns
- Filter by aggregated values
- Simple iteration of rows
- Object graph based traversal for each row
- Create new data table from describe
- Import and export to CSV
- Import and export to JSON Lines
- Unmarshal to untyped objects
- Unmarshal to typed objects
package main
import (
_ "embed"
"bytes"
"encoding/csv"
"fmt"
"github.com/shellyln/go-graphdt/datatable"
"github.com/shellyln/go-graphdt/datatable/runtime"
"github.com/shellyln/go-graphdt/datatable/types"
)
//go:embed _testdata/test1.csv
var csv1Bytes []byte
//go:embed _testdata/test2.csv
var csv2Bytes []byte
func main() {
ctx := runtime.NewRuntimeContext()
dt1 := datatable.NewDataTableWithSize(
ctx,
1000, 1000,
types.Type_Nullable_String,
types.Type_Nullable_I64,
types.Type_Nullable_F64,
)
dt1.SetSimpleHeader([]string{"Foo", "Bar", "Baz"})
dt2 := datatable.NewDataTableWithSize(
ctx,
1000
8051
, 1000,
types.Type_Nullable_String,
types.Type_Nullable_String,
types.Type_Nullable_I64,
types.Type_Nullable_F64,
)
dt2.SetSimpleHeader([]string{"Foo", "Qux", "Quux", "Corge"})
buf1 := bytes.NewReader(csv1Bytes)
reader1 := csv.NewReader(buf1)
if err := dt1.AppendFromCSV(reader1, datatable.CSVOptions{HasHeader: true}); err != nil {
fmt.Printf("error = %v\n", err)
return
}
err = dt1.Filter([]types.FilterInfo{
{Op: types.Op_LoadCol, Col: 1},
{Op: types.Op_LoadImmediate, Param: 63},
{Op: types.Op_Lt},
{Op: types.Op_LoadCol, Col: 1},
{Op: types.Op_LoadImmediate, Param: 64},
{Op: types.Op_Gt},
{Op: types.Op_Or},
}...)
if err != nil {
fmt.Printf("error = %v\n", err)
return
}
err = dt1.Sort([]types.SortInfo{
{Col: 0, Desc: false, NullsLast: true},
{Col: 2},
}...)
if err != nil {
fmt.Printf("error = %v\n", err)
return
}
buf2 := bytes.NewReader(csv2Bytes)
reader2 := csv.NewReader(buf2)
if err := dt2.AppendFromCSV(reader2, datatable.CSVOptions{HasHeader: true}); err != nil {
fmt.Printf("error = %v\n", err)
return
}
result, err := dt1.LeftJoin(0, dt2, 0, "quxes", datatable.JoinOptions{})
if err != nil {
fmt.Printf("error = %v\n", err)
return
}
var dst []Foo
if err := dtFoo6.Unmarshal(&dst); err != nil {
t.Errorf("error = %v\n", err)
return
}
}MIT
Copyright (c) 2023 Shellyl_N and Authors.