func (u *updateNode) Next() (bool, error) {
next, err := u.run.rows.Next()
if !next {
if err == nil {
// We're done. Finish the batch.
err = u.tw.finalize(u.p.ctx())
}
return false, err
}
if u.run.explain == explainDebug {
return true, nil
}
tracing.AnnotateTrace()
oldValues := u.run.rows.Values()
// Our updated value expressions occur immediately after the plain
// columns in the output.
updateValues := oldValues[len(u.tw.ru.fetchCols):]
oldValues = oldValues[:len(u.tw.ru.fetchCols)]
u.checkHelper.loadRow(u.tw.ru.fetchColIDtoRowIndex, oldValues, false)
u.checkHelper.loadRow(u.updateColsIdx, updateValues, true)
if err := u.checkHelper.check(&u.p.evalCtx); err != nil {
return false, err
}
// Ensure that the values honor the specified column widths.
for i := range updateValues {
if err := sqlbase.CheckValueWidth(u.tw.ru.updateCols[i], updateValues[i]); err != nil {
return false, err
}
}
// Update the row values.
for i, col := range u.tw.ru.updateCols {
val := updateValues[i]
if !col.Nullable && val == parser.DNull {
return false, sqlbase.NewNonNullViolationError(col.Name)
}
}
newValues, err := u.tw.row(u.p.ctx(), append(oldValues, updateValues...))
if err != nil {
return false, err
}
resultRow, err := u.rh.cookResultRow(newValues)
if err != nil {
return false, err
}
u.run.resultRow = resultRow
return true, nil
}
// GenerateInsertRow prepares a row tuple for insertion. It fills in default
// expressions, verifies non-nullable columns, and checks column widths.
func GenerateInsertRow(
defaultExprs []parser.TypedExpr,
insertColIDtoRowIndex map[sqlbase.ColumnID]int,
insertCols []sqlbase.ColumnDescriptor,
evalCtx parser.EvalContext,
tableDesc *sqlbase.TableDescriptor,
rowVals parser.DTuple,
) (parser.DTuple, error) {
// The values for the row may be shorter than the number of columns being
// inserted into. Generate default values for those columns using the
// default expressions.
if len(rowVals) < len(insertCols) {
// It's not cool to append to the slice returned by a node; make a copy.
oldVals := rowVals
rowVals = make(parser.DTuple, len(insertCols))
copy(rowVals, oldVals)
for i := len(oldVals); i < len(insertCols); i++ {
if defaultExprs == nil {
rowVals[i] = parser.DNull
continue
}
d, err := defaultExprs[i].Eval(&evalCtx)
if err != nil {
return nil, err
}
rowVals[i] = d
}
}
// Check to see if NULL is being inserted into any non-nullable column.
for _, col := range tableDesc.Columns {
if !col.Nullable {
if i, ok := insertColIDtoRowIndex[col.ID]; !ok || rowVals[i] == parser.DNull {
return nil, sqlbase.NewNonNullViolationError(col.Name)
}
}
}
// Ensure that the values honor the specified column widths.
for i := range rowVals {
if err := sqlbase.CheckValueWidth(insertCols[i], rowVals[i]); err != nil {
return nil, err
}
}
return rowVals, nil
}
// truncateAndBackfillColumnsChunk returns the next-key, done and an error.
// next-key and done are invalid if error != nil. next-key is invalid if done
// is true.
func (sc *SchemaChanger) truncateAndBackfillColumnsChunk(
added []sqlbase.ColumnDescriptor,
dropped []sqlbase.ColumnDescriptor,
defaultExprs []parser.TypedExpr,
sp roachpb.Span,
updateValues parser.DTuple,
nonNullViolationColumnName string,
chunkSize int64,
mutationIdx int,
lastCheckpoint *time.Time,
) (roachpb.Key, bool, error) {
done := false
var nextKey roachpb.Key
err := sc.db.Txn(context.TODO(), func(txn *client.Txn) error {
if sc.testingKnobs.RunBeforeBackfillChunk != nil {
if err := sc.testingKnobs.RunBeforeBackfillChunk(sp); err != nil {
return err
}
}
if sc.testingKnobs.RunAfterBackfillChunk != nil {
defer sc.testingKnobs.RunAfterBackfillChunk()
}
tableDesc, err := sqlbase.GetTableDescFromID(txn, sc.tableID)
if err != nil {
return err
}
// Short circuit the backfill if the table has been deleted.
if done = tableDesc.Dropped(); done {
return nil
}
updateCols := append(added, dropped...)
fkTables := tablesNeededForFKs(*tableDesc, CheckUpdates)
for k := range fkTables {
table, err := sqlbase.GetTableDescFromID(txn, k)
if err != nil {
return err
}
fkTables[k] = tableLookup{table: table}
}
// TODO(dan): Tighten up the bound on the requestedCols parameter to
// makeRowUpdater.
requestedCols := make([]sqlbase.ColumnDescriptor, 0, len(tableDesc.Columns)+len(added))
requestedCols = append(requestedCols, tableDesc.Columns...)
requestedCols = append(requestedCols, added...)
ru, err := makeRowUpdater(
txn, tableDesc, fkTables, updateCols, requestedCols, rowUpdaterOnlyColumns,
)
if err != nil {
return err
}
// TODO(dan): This check is an unfortunate bleeding of the internals of
// rowUpdater. Extract the sql row to k/v mapping logic out into something
// usable here.
if !ru.isColumnOnlyUpdate() {
panic("only column data should be modified, but the rowUpdater is configured otherwise")
}
// Run a scan across the table using the primary key. Running
// the scan and applying the changes in many transactions is
// fine because the schema change is in the correct state to
// handle intermediate OLTP commands which delete and add
// values during the scan.
var rf sqlbase.RowFetcher
colIDtoRowIndex := colIDtoRowIndexFromCols(tableDesc.Columns)
valNeededForCol := make([]bool, len(tableDesc.Columns))
for i := range valNeededForCol {
_, valNeededForCol[i] = ru.fetchColIDtoRowIndex[tableDesc.Columns[i].ID]
}
if err := rf.Init(
tableDesc, colIDtoRowIndex, &tableDesc.PrimaryIndex, false, false,
tableDesc.Columns, valNeededForCol,
); err != nil {
return err
}
if err := rf.StartScan(
txn, roachpb.Spans{sp}, true /* limit batches */, chunkSize,
); err != nil {
return err
}
oldValues := make(parser.DTuple, len(ru.fetchCols))
writeBatch := txn.NewBatch()
rowLength := 0
var lastRowSeen parser.DTuple
i := int64(0)
for ; i < chunkSize; i++ {
row, err := rf.NextRow()
if err != nil {
return err
}
if row == nil {
break
}
lastRowSeen = row
if nonNullViolationColumnName != "" {
return sqlbase.NewNonNullViolationError(nonNullViolationColumnName)
}
copy(oldValues, row)
// Update oldValues with NULL values where values weren't found;
// only update when necessary.
if rowLength != len(row) {
rowLength = len(row)
for j := rowLength; j < len(oldValues); j++ {
oldValues[j] = parser.DNull
}
}
if _, err := ru.updateRow(txn.Context, writeBatch, oldValues, updateValues); err != nil {
return err
}
}
if err := txn.Run(writeBatch); err != nil {
return convertBackfillError(tableDesc, writeBatch)
}
if done = i < chunkSize; done {
return nil
}
curIndexKey, _, err := sqlbase.EncodeIndexKey(
tableDesc, &tableDesc.PrimaryIndex, colIDtoRowIndex, lastRowSeen,
sqlbase.MakeIndexKeyPrefix(tableDesc, tableDesc.PrimaryIndex.ID))
if err != nil {
return err
}
resume := roachpb.Span{Key: roachpb.Key(curIndexKey).PrefixEnd(), EndKey: sp.EndKey}
if err := sc.maybeWriteResumeSpan(txn, tableDesc, resume, mutationIdx, lastCheckpoint); err != nil {
return err
}
nextKey = resume.Key
return nil
})
return nextKey, done, err
}
func (n *insertNode) Next() (bool, error) {
ctx := n.editNodeBase.p.ctx()
if next, err := n.run.rows.Next(); !next {
if err == nil {
// We're done. Finish the batch.
err = n.tw.finalize(ctx)
}
return false, err
}
if n.run.explain == explainDebug {
return true, nil
}
rowVals := n.run.rows.Values()
// The values for the row may be shorter than the number of columns being
// inserted into. Generate default values for those columns using the
// default expressions.
if len(rowVals) < len(n.insertCols) {
// It's not cool to append to the slice returned by a node; make a copy.
oldVals := rowVals
rowVals = make(parser.DTuple, len(n.insertCols))
copy(rowVals, oldVals)
for i := len(oldVals); i < len(n.insertCols); i++ {
if n.defaultExprs == nil {
rowVals[i] = parser.DNull
continue
}
d, err := n.defaultExprs[i].Eval(&n.p.evalCtx)
if err != nil {
return false, err
}
rowVals[i] = d
}
}
// Check to see if NULL is being inserted into any non-nullable column.
for _, col := range n.tableDesc.Columns {
if !col.Nullable {
if i, ok := n.insertColIDtoRowIndex[col.ID]; !ok || rowVals[i] == parser.DNull {
return false, sqlbase.NewNonNullViolationError(col.Name)
}
}
}
// Ensure that the values honor the specified column widths.
for i := range rowVals {
if err := sqlbase.CheckValueWidth(n.insertCols[i], rowVals[i]); err != nil {
return false, err
}
}
n.checkHelper.loadRow(n.insertColIDtoRowIndex, rowVals, false)
if err := n.checkHelper.check(&n.p.evalCtx); err != nil {
return false, err
}
_, err := n.tw.row(ctx, rowVals)
if err != nil {
return false, err
}
for i, val := range rowVals {
if n.run.rowTemplate != nil {
n.run.rowTemplate[n.run.rowIdxToRetIdx[i]] = val
}
}
resultRow, err := n.rh.cookResultRow(n.run.rowTemplate)
if err != nil {
return false, err
}
n.run.resultRow = resultRow
return true, nil
}