insert - Does Oracle Synonyms for table cause a race conditions? -


i have use synonym table in remote database. application in remote site insert data source table, , application read data via synonym of table.

remote site application send tcp message after inserting record source table. application execute fetch once received message. detect records fail fetch because not available in table (synonym) @ time of tcp message received.

is there possibility of having race condition in inserting , fetching in synonyms ?

the presence (or absence) of synonym has no impact.

if source application commits before sending notification , if application using default read committed transaction isolation level, application see rows committed when queries database. exception aware of if remote database rac database max_commit_propagation_delay set non-zero value. unless remote database older (pre-10.2) version of oracle, case if had changed default value parameter.

you can determine oracle version looking @ v$version

select * v$version

you can determine whether max_commit_propagation_delay has been set querying v$parameter (this return 0 rows if parameter has not been set)

select name, value v$parameter name = 'max_commit_propagation_delay'

you can determine whether database multi-node rac cluster querying gv$instance. if returns count(*) of greater 1, multi-node rac database

select count(*) gv$instance

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