func (s *DeleteStmt) hitWhere(ctx context.Context, fields []*field.ResultField, data []interface{}) (bool, error) {
if s.Where == nil {
return true, nil
}
m := map[interface{}]interface{}{}
m[expression.ExprEvalIdentFunc] = func(name string) (interface{}, error) {
return plans.GetIdentValue(name, fields, data, field.DefaultFieldFlag)
}
ok, err := expression.EvalBoolExpr(ctx, s.Where, m)
if err != nil {
return false, errors.Trace(err)
}
return ok, nil
}
// Exec implements the stmt.Statement Exec interface.
func (s *UpdateStmt) Exec(ctx context.Context) (_ rset.Recordset, err error) {
p, err := s.plan(ctx)
if err != nil {
return nil, errors.Trace(err)
}
defer p.Close()
updatedRowKeys := make(map[string]bool)
// Get table alias map.
fs := p.GetFields()
columns, err0 := getUpdateColumns(s.List, fs)
if err0 != nil {
return nil, errors.Trace(err0)
}
m := map[interface{}]interface{}{}
var records []*plan.Row
for {
row, err1 := p.Next(ctx)
if err1 != nil {
return nil, errors.Trace(err1)
}
if row == nil {
break
}
if len(row.RowKeys) == 0 {
// Nothing to update
continue
}
records = append(records, row)
}
for _, row := range records {
rowData := row.Data
// Set EvalIdentFunc
m[expression.ExprEvalIdentFunc] = func(name string) (interface{}, error) {
return plans.GetIdentValue(name, p.GetFields(), rowData, field.DefaultFieldFlag)
}
// Update rows
offset := 0
for _, entry := range row.RowKeys {
tbl := entry.Tbl
k := entry.Key
lastOffset := offset
offset += len(tbl.Cols())
data := rowData[lastOffset:offset]
_, ok := updatedRowKeys[k]
if ok {
// Each matching row is updated once, even if it matches the conditions multiple times.
continue
}
// Update row
handle, err2 := util.DecodeHandleFromRowKey(k)
if err2 != nil {
return nil, errors.Trace(err2)
}
err2 = updateRecord(ctx, handle, data, tbl, columns, m, lastOffset, false)
if err2 != nil {
return nil, errors.Trace(err2)
}
updatedRowKeys[k] = true
}
}
return nil, nil
}
// Exec implements the stmt.Statement Exec interface.
func (s *UpdateStmt) Exec(ctx context.Context) (_ rset.Recordset, err error) {
p, err := s.plan(ctx)
if err != nil {
return nil, errors.Trace(err)
}
defer p.Close()
updatedRowKeys := make(map[string]bool)
for {
row, err1 := p.Next(ctx)
if err1 != nil {
return nil, errors.Trace(err1)
}
if row == nil {
break
}
rowData := row.Data
if len(row.RowKeys) == 0 {
// Nothing to update
return nil, nil
}
// Set EvalIdentFunc
m := make(map[interface{}]interface{})
m[expressions.ExprEvalIdentFunc] = func(name string) (interface{}, error) {
return plans.GetIdentValue(name, p.GetFields(), rowData, field.DefaultFieldFlag)
}
// Update rows
start := 0
for _, entry := range row.RowKeys {
tbl := entry.Tbl
k := entry.Key
_, ok := updatedRowKeys[k]
if ok {
// Each matching row is updated once, even if it matches the conditions multiple times.
continue
}
// Update row
handle, err2 := util.DecodeHandleFromRowKey(k)
if err2 != nil {
return nil, errors.Trace(err2)
}
end := start + len(tbl.Cols())
data := rowData[start:end]
start = end
tcols, err2 := getUpdateColumns(tbl, s.List, s.MultipleTable)
if err2 != nil {
return nil, errors.Trace(err2)
}
if len(tcols) == 0 {
// Nothing to update for this table.
continue
}
// Get data in the table
err2 = updateRecord(ctx, handle, data, tbl, tcols, s.List, nil, m)
if err2 != nil {
return nil, errors.Trace(err2)
}
updatedRowKeys[k] = true
}
}
return nil, nil
}