Thread: Please help to speed up UPDATE statement
The following statement runs VERY slowly on large tables. Any idea how to speed it up ? UPDATE rid SET dokumnr=NULL WHERE dokumnr NOT IN (SELECT dokumnr FROM dok); Tables: CREATE TABLE dok ( dokumnr INTEGER, CONSTRAINT dok_pkey PRIMARY KEY (dokumnr) ); CREATE TABLE rid ( dokumnr INTEGER ); CREATE INDEX rid_dokumnr_idx ON rid (dokumnr); Andrus
On Apr 12, 2005 9:40 AM, Andrus <noeetasoftspam@online.ee> wrote:
The following statement runs VERY slowly on large tables.
Any idea how to speed it up ?
UPDATE rid SET dokumnr=NULL WHERE
dokumnr NOT IN (SELECT dokumnr FROM dok);
Tables:
CREATE TABLE dok ( dokumnr INTEGER,
CONSTRAINT dok_pkey PRIMARY KEY (dokumnr) );
CREATE TABLE rid ( dokumnr INTEGER );
CREATE INDEX rid_dokumnr_idx ON rid (dokumnr);
Andrus
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