Question

I’m using a quite straightforward setup to generate a CSV file from a SELECT query. How do I reduce (or at least control) the time window where the query locks the database for reads?

Here’s a typical example:

private List<String[]> getData(final ResultSet rs) throws SQLException {
    final List<String[]> res = new LinkedList<String[]>();
    int i = 0;
    int stride = 10;
    while (rs.next()) {
        if (++i % stride == 0) {
            System.out.println("Row " + i);
        }
        if (i >= stride * 10) {
            stride = stride * 10;
        }
        res.add(getRow(rs));
    }
    System.out.println("*** Total " + i + " rows");
    return res;
}

Answer 1

JDBC Transaction Isolation levels

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