Function NewRowDecoder

pkg/executor/builder.go:5467–5517

NewRowDecoder creates a chunk decoder for new row format row value decode.

(ctx sessionctx.Context, schema *expression.Schema, tbl *model.TableInfo)

// NewRowDecoder creates a chunk decoder for new row format row value decode.
func NewRowDecoder(ctx sessionctx.Context, schema *expression.Schema, tbl *model.TableInfo) *rowcodec.ChunkDecoder {
	getColInfoByID := func(tbl *model.TableInfo, colID int64) *model.ColumnInfo {
		for _, col := range tbl.Columns {
			if col.ID == colID {
				return col
			}
		}
		return nil
	}
	var pkCols []int64
	reqCols := make([]rowcodec.ColInfo, len(schema.Columns))
	for i := range schema.Columns {
		idx, col := i, schema.Columns[i]
		isPK := (tbl.PKIsHandle && mysql.HasPriKeyFlag(col.RetType.GetFlag())) || col.ID == model.ExtraHandleID
		if isPK {
			pkCols = append(pkCols, col.ID)
		}
		isGeneratedCol := false
		if col.VirtualExpr != nil {
			isGeneratedCol = true
		}
		reqCols[idx] = rowcodec.ColInfo{
			ID:            col.ID,
			VirtualGenCol: isGeneratedCol,
			Ft:            col.RetType,
		}
	}
	if len(pkCols) == 0 {
		pkCols = tables.TryGetCommonPkColumnIds(tbl)
		if len(pkCols) == 0 {
			pkCols = []int64{-1}
		}
	}
	defVal := func(i int, chk *chunk.Chunk) error {
		if reqCols[i].ID < 0 {
			// model.ExtraHandleID, ExtraPhysTblID... etc
			// Don't set the default value for that column.
			chk.AppendNull(i)
			return nil
		}

		ci := getColInfoByID(tbl, reqCols[i].ID)
		d, err := table.GetColOriginDefaultValue(ctx.GetExprCtx(), ci)
		if err != nil {
			return err
		}
		chk.AppendDatum(i, &d)
		return nil
	}
	return rowcodec.NewChunkDecoder(reqCols, pkCols, defVal, ctx.GetSessionVars().Location())
}

func (b *executorBuilder) buildBatchPointGet(plan *plannercore.BatchPointGetPlan) exec.Executor {
	var err error