func (sei *session) limitSelectResult(r *mysql.Resultset, count, offset int64) {
// rewrite count, remove bad index range
if offset+count > int64(len(r.Values)) {
count = int64(len(r.Values)) - offset
}
r.Values = r.Values[offset : offset+count]
r.RowDatas = r.RowDatas[offset : offset+count]
}
func (sei *session) buildResultset(fields []*mysql.Field, names []string, values [][]interface{}) (*mysql.Resultset, error) {
var ExistFields bool
r := new(mysql.Resultset)
r.Fields = make([]*mysql.Field, len(names))
//use the field def that get from true database
if len(fields) != 0 {
if len(r.Fields) == len(fields) {
ExistFields = true
} else {
return nil, mysql.ErrInvalidArgument
}
}
var b []byte
var err error
for i, vs := range values {
if len(vs) != len(r.Fields) {
return nil, fmt.Errorf("row %d has %d column not equal %d", i, len(vs), len(r.Fields))
}
var row []byte
for j, value := range vs {
// column define
if i == 0 {
if ExistFields {
r.Fields[j] = fields[j]
} else {
field := &mysql.Field{}
r.Fields[j] = field
field.Name = []byte(names[j])
if err = formatField(field, value); err != nil {
return nil, err
}
}
}
b, err = formatValue(value)
if err != nil {
return nil, err
}
row = append(row, mysql.PutLengthEncodedString(b)...)
}
r.RowDatas = append(r.RowDatas, row)
}
return r, nil
}
func (sei *session) sortResultSet(set *mysql.Resultset, stmt *sqlparser.Select) error {
if len(stmt.OrderBy) > 0 {
glog.Info("Sort select results")
ks := make([]mysql.SortKey, 0, len(stmt.OrderBy))
for _, o := range stmt.OrderBy {
ks = append(ks, mysql.SortKey{
Direction: o.Direction,
Name: sqlparser.String(o.Expr),
})
}
return set.Sort(ks)
}
return nil
}
func (sei *session) buildEmptySet(names []string, t []interface{}) (*mysql.Resultset, error) {
r := new(mysql.Resultset)
r.Fields = make([]*mysql.Field, len(names))
for n, name := range names {
field := &mysql.Field{}
r.Fields[n] = field
field.Name = []byte(name)
if err := formatField(field, t[n]); err != nil {
return nil, err
}
}
return r, nil
}