1
0
mirror of https://github.com/uptrace/go-clickhouse.git synced 2025-06-08 23:26:11 +02:00
go-clickhouse/ch/chschema/column_nullable.go

101 lines
2.1 KiB
Go
Raw Normal View History

2022-01-23 09:36:24 +02:00
package chschema
import (
"reflect"
"github.com/uptrace/go-clickhouse/ch/chproto"
)
type NullableColumn struct {
Nulls Uint8Column
Values Columnar
nullable reflect.Value // reflect.Slice
}
func NullableNewColumnFunc(fn NewColumnFunc) NewColumnFunc {
return func(typ reflect.Type, chType string, numRow int) Columnar {
return &NullableColumn{
Values: fn(typ, chType, numRow),
}
}
}
var _ Columnar = (*NullableColumn)(nil)
func (c *NullableColumn) Type() reflect.Type {
return reflect.PtrTo(c.Values.Type())
}
func (c *NullableColumn) Set(v any) {
panic("not reached")
}
func (c *NullableColumn) AppendValue(v reflect.Value) {
if v.IsNil() {
c.Nulls.Column = append(c.Nulls.Column, 1)
c.Values.AppendValue(reflect.New(c.Values.Type()).Elem())
} else {
c.Nulls.Column = append(c.Nulls.Column, 0)
c.Values.AppendValue(v.Elem())
}
}
func (c *NullableColumn) Value() any {
return c.nullable.Interface()
}
func (c *NullableColumn) Nullable(nulls Uint8Column) any {
panic("not implemented")
}
func (c *NullableColumn) Len() int {
return c.Values.Len()
}
func (c *NullableColumn) Index(idx int) any {
elem := c.nullable.Index(idx)
if elem.IsNil() {
return nil
}
return elem.Elem().Interface()
}
func (c *NullableColumn) Slice(s, e int) any {
panic("not implemented")
}
func (c *NullableColumn) ConvertAssign(idx int, dest reflect.Value) error {
if idx < len(c.Nulls.Column) && c.Nulls.Column[idx] == 1 {
return nil
}
if dest.IsNil() {
dest.Set(reflect.New(dest.Type().Elem()))
}
return c.Values.ConvertAssign(idx, dest.Elem())
}
func (c *NullableColumn) ReadFrom(rd *chproto.Reader, numRow int) error {
if numRow == 0 {
return nil
}
if err := c.Nulls.ReadFrom(rd, numRow); err != nil {
return err
}
if err := c.Values.ReadFrom(rd, numRow); err != nil {
return err
}
c.nullable = reflect.ValueOf(c.Values.Nullable(c.Nulls))
return nil
}
func (c *NullableColumn) WriteTo(wr *chproto.Writer) error {
if err := c.Nulls.WriteTo(wr); err != nil {
return err
}
return c.Values.WriteTo(wr)
}
func isNilValue(v reflect.Value) bool {
return false
}