示例#1
0
func (m *MockCsvSource) loadTable(tableName string) error {

	csvRaw, ok := m.raw[tableName]
	if !ok {
		return schema.ErrNotFound
	}
	sr := strings.NewReader(csvRaw)
	u.Debugf("mockcsv:%p load mockcsv: %q  data:%v", m, tableName, csvRaw)
	csvSource, _ := datasource.NewCsvSource(tableName, 0, sr, make(<-chan bool, 1))
	tbl := membtree.NewStaticData(tableName)
	u.Infof("loaded columns %v", csvSource.Columns())
	tbl.SetColumns(csvSource.Columns())
	//u.Infof("set index col for %v: %v -- %v", tableName, 0, csvSource.Columns()[0])
	m.tables[tableName] = tbl

	// Now we are going to page through the Csv rows and Put into
	//  Static Data Source, ie copy into memory btree structure
	for {
		msg := csvSource.Next()
		if msg == nil {
			//u.Infof("table:%v  len=%v", tableName, tbl.Length())
			return nil
		}
		dm, ok := msg.Body().(*datasource.SqlDriverMessageMap)
		if !ok {
			return fmt.Errorf("Expected *datasource.SqlDriverMessageMap but got %T", msg.Body())
		}

		// We don't know the Key
		tbl.Put(nil, nil, dm.Values())
	}
	return nil
}
示例#2
0
func (m *csvStaticSource) Open(connInfo string) (schema.Conn, error) {
	if data, ok := m.testData[connInfo]; ok {
		sr := strings.NewReader(data)
		return datasource.NewCsvSource(connInfo, 0, sr, make(<-chan bool, 1))
	}
	return nil, fmt.Errorf("not found")
}
示例#3
0
func (m *MockCsvSource) Open(connInfo string) (datasource.SourceConn, error) {
	if data, ok := m.data[connInfo]; ok {
		sr := strings.NewReader(data)
		u.Debugf("open mockcsv: %v", connInfo)
		return datasource.NewCsvSource(sr, make(<-chan bool, 1))
	}
	u.Errorf("not found?  %v", connInfo)
	return nil, fmt.Errorf("not found")
}
示例#4
0
func main() {

	if sqlText == "" {
		u.Errorf("You must provide a valid select query in argument:    --sql=\"select ...\"")
		return
	}

	// load all of our built-in functions
	builtins.LoadAllBuiltins()

	// Add a custom function to the VM to make available to SQL language
	expr.FuncAdd("email_is_valid", EmailIsValid)

	// Our file source of csv's is stdin
	stdIn, err := os.Open("/dev/stdin")
	if err != nil {
		u.Errorf("could not open stdin? %v", err)
		return
	}

	// We are registering the "csv" datasource, to show that
	// the backend/sources can be easily created/added.  This csv
	// reader is an example datasource that is very, very simple.
	exit := make(chan bool)
	src, _ := datasource.NewCsvSource("stdin", 0, stdIn, exit)
	datasource.Register("csv", src)

	db, err := sql.Open("qlbridge", "csv:///dev/stdin")
	if err != nil {
		panic(err.Error())
	}
	defer db.Close()

	rows, err := db.Query(sqlText)
	if err != nil {
		u.Errorf("could not execute query: %v", err)
		return
	}
	defer rows.Close()
	cols, _ := rows.Columns()

	// this is just stupid hijinx for getting pointers for unknown len columns
	readCols := make([]interface{}, len(cols))
	writeCols := make([]string, len(cols))
	for i, _ := range writeCols {
		readCols[i] = &writeCols[i]
	}
	fmt.Printf("\n\nScanning through CSV: (%v)\n\n", strings.Join(cols, ","))
	for rows.Next() {
		rows.Scan(readCols...)
		fmt.Println(strings.Join(writeCols, ", "))
	}
	fmt.Println("")
}