The upload_fetch script is a SELECT statement that defines a cursor in the consolidated database table. This cursor is used to compare the old values of updated rows, as received from the remote database, against the value in the consolidated database. In this way, the upload_fetch script identifies conflicts when updates are being processed.

Given a synchronized table defined as:

CREATE TABLE uf_example (
 pk1 integer NOT NULL,
 pk2  integer NOT NULL,
 val  varchar(200),
 PRIMARY KEY( pk1, pk2 ));

Then one possible upload_fetch script for this table is:

SELECT pk1, pk2, val
FROM uf_example
WHERE pk1 = {ml r.pk1} and pk2 = {ml r.pk2}

See upload_fetch table event.

The MobiLink server requires the WHERE clause of the query in the upload_fetch script to identify exactly one row in the consolidated database to be checked for conflicts.