Method run

copy_from.go:118–215

(ctx context.Context)

}

func (ct *copyFrom) run(ctx context.Context) (int64, error) {
	if ct.conn.copyFromTracer != nil {
		ctx = ct.conn.copyFromTracer.TraceCopyFromStart(ctx, ct.conn, TraceCopyFromStartData{
			TableName:   ct.tableName,
			ColumnNames: ct.columnNames,
		})
	}

	quotedTableName := ct.tableName.Sanitize()
	cbuf := &bytes.Buffer{}
	for i, cn := range ct.columnNames {
		if i != 0 {
			cbuf.WriteString(", ")
		}
		cbuf.WriteString(quoteIdentifier(cn))
	}
	quotedColumnNames := cbuf.String()

	var sd *pgconn.StatementDescription
	switch ct.mode {
	case QueryExecModeExec, QueryExecModeSimpleProtocol:
		// These modes don't support the binary format. Before the inclusion of the
		// QueryExecModes, Conn.Prepare was called on every COPY operation to get
		// the OIDs. These prepared statements were not cached.
		//
		// Since that's the same behavior provided by QueryExecModeDescribeExec,
		// we'll default to that mode.
		ct.mode = QueryExecModeDescribeExec
		fallthrough
	case QueryExecModeCacheStatement, QueryExecModeCacheDescribe, QueryExecModeDescribeExec:
		var err error
		sd, err = ct.conn.getStatementDescription(
			ctx,
			ct.mode,
			fmt.Sprintf("select %s from %s", quotedColumnNames, quotedTableName),
		)
		if err != nil {
			return 0, fmt.Errorf("statement description failed: %w", err)
		}
	default:
		return 0, fmt.Errorf("unknown QueryExecMode: %v", ct.mode)
	}

	r, w := io.Pipe()
	doneChan := make(chan struct{})

	go func() {
		defer close(doneChan)

		// Purposely NOT using defer w.Close(). See https://github.com/golang/go/issues/24283.
		buf := ct.conn.wbuf

		buf = append(buf, "PGCOPY\n\377\r\n\000"...)
		buf = pgio.AppendInt32(buf, 0)
		buf = pgio.AppendInt32(buf, 0)

		moreRows := true
		for moreRows {