func updateRecord(ctx context.Context, h int64, oldData, newData []types.Datum, assignFlag []bool, t table.Table, offset int, onDuplicateUpdate bool) error {
cols := t.Cols()
touched := make(map[int]bool, len(cols))
assignExists := false
sc := ctx.GetSessionVars().StmtCtx
var newHandle types.Datum
for i, hasSetExpr := range assignFlag {
if !hasSetExpr {
if onDuplicateUpdate {
newData[i] = oldData[i]
}
continue
}
if i < offset || i >= offset+len(cols) {
// The assign expression is for another table, not this.
continue
}
colIndex := i - offset
col := cols[colIndex]
if col.IsPKHandleColumn(t.Meta()) {
newHandle = newData[i]
}
if mysql.HasAutoIncrementFlag(col.Flag) {
if newData[i].IsNull() {
return errors.Errorf("Column '%v' cannot be null", col.Name.O)
}
val, err := newData[i].ToInt64(sc)
if err != nil {
return errors.Trace(err)
}
t.RebaseAutoID(val, true)
}
touched[colIndex] = true
assignExists = true
}
// If no assign list for this table, no need to update.
if !assignExists {
return nil
}
// Check whether new value is valid.
if err := table.CastValues(ctx, newData, cols, false); err != nil {
return errors.Trace(err)
}
if err := table.CheckNotNull(cols, newData); err != nil {
return errors.Trace(err)
}
// If row is not changed, we should do nothing.
rowChanged := false
for i := range oldData {
if !touched[i] {
continue
}
n, err := newData[i].CompareDatum(sc, oldData[i])
if err != nil {
return errors.Trace(err)
}
if n != 0 {
rowChanged = true
break
}
}
if !rowChanged {
// See https://dev.mysql.com/doc/refman/5.7/en/mysql-real-connect.html CLIENT_FOUND_ROWS
if ctx.GetSessionVars().ClientCapability&mysql.ClientFoundRows > 0 {
sc.AddAffectedRows(1)
}
return nil
}
var err error
if !newHandle.IsNull() {
err = t.RemoveRecord(ctx, h, oldData)
if err != nil {
return errors.Trace(err)
}
_, err = t.AddRecord(ctx, newData)
} else {
// Update record to new value and update index.
err = t.UpdateRecord(ctx, h, oldData, newData, touched)
}
if err != nil {
return errors.Trace(err)
}
dirtyDB := getDirtyDB(ctx)
tid := t.Meta().ID
dirtyDB.deleteRow(tid, h)
dirtyDB.addRow(tid, h, newData)
// Record affected rows.
if !onDuplicateUpdate {
sc.AddAffectedRows(1)
} else {
sc.AddAffectedRows(2)
}
return nil
}