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Re: sql statements using access frontend

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On 02/12/11 14:02, Gavin Mitchell wrote:
But if the data is changed within the table itself or a form based on
the table or query it starts a transaction and adds all available fields
into the where clause

2011-12-01 10:03:52 GMT LOG: statement: BEGIN;UPDATE
"ua"."pole_survey_tbl" SET "completedby"=E'test' WHERE "pole_survey_id"
= 6478 AND "survey_id" = 1025 and (etc…….)

I chopped the log entry short but there are AND entries fo all fields in
the table

It's an implementation of "optimistic locking". Imagine we are both updating the same row at the same time. If my update gets committed before yours, then yours won't find a row to update. Otherwise my changes could be overwritten without you knowing.

--
  Richard Huxton
  Archonet Ltd

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