strange behaviour: #1146 but an insert some lines before was successful

[Jan Pilarzeck]

Hi there,

got a really strange behaviour with MySQL 4.0.18 and PHP - the script does the following:

1. insert a row into table xxx
2. get last_insert_id
3. do some other things
4. update the row from step 1 with sql like this:
UPDATE xxx SET yyy = 'somevalue' WHERE id = 456
id is the result of step 2

now the error: the result of the query of step 4 is "false" with the error-code #1146 - "table yyy doesn't exist".

but this occurs not always - approximately 10-15% of all script runs are NOT successful.

i wrote a logging of all sql-queries of stept 4 - the result:

all generated sql-queries have correct syntax and complete. copy&paste to the mysql-console, execute and the row was updated as it should be. also the id from step 2 was always the correct one, never wrong or even empty or null.

some further informations:
- the problem occur on different days at different times
- mysql-server already re-started
- installed new newer build for same version
- for all database-related actions the script uses the same object with the same mysql-connection
- between step 2 and step 4 there are only a few lines with some simple "if() {}" and some string-operations and NOTHING else is done in the database or with the db-object
- so shortend to db-related actions the actions are: insert - get id - update

any ideas?