From: | Kevin Murphy <murphy(at)genome(dot)chop(dot)edu> |
---|---|
To: | PostgreSQL general <pgsql-general(at)postgresql(dot)org> |
Subject: | CLUSTER equivalent |
Date: | 2005-08-02 13:11:46 |
Message-ID: | 42EF7112.9040300@genome.chop.edu |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
Are the two following options equivalent?
OPTION A (ordered insert):
CREATE TABLE table1 (cluster_col TEXT, col2 INTEGER);
CREATE INDEX idx1 ON table1(cluster_col);
INSERT INTO table1 (cluster_col, col2) SELECT cluster_col, col2 FROM
table1 ORDER BY cluster_col;
OPTION B (unordered insert followed by CLUSTER):
CREATE TABLE table1 (cluster_col TEXT, col2 INTEGER);
CREATE INDEX idx1 ON table1(cluster_col);
INSERT INTO table1 (cluster_col, col2) SELECT cluster_col, col2 FROM table1;
CLUSTER idx1 ON table1;
Thanks,
Kevin Murphy
P.S. On another topic, did I gather correctly from a recent thread that
it would be more efficient to define the above table (if it were really
only two columns) as:
create table clustered_tagged_genes (integer pmid, text mention);
i.e., with the integer field before the text field?
From | Date | Subject | |
---|---|---|---|
Next Message | Michael Fuhr | 2005-08-02 13:16:34 | Re: Problem with dropping a tablespace |
Previous Message | Samuel Thoraval | 2005-08-02 13:10:20 | System catalog diagram |