What is the isolation attribute in the cftransaction tag for?
The isolation attribute is used to specify how that transaction will behave with regard to database locking. I’ll try to provide a very brief, general (and incomplete) description; the details may vary slightly between database servers. There are four possible values: READ_UNCOMMITTED means that the transaction will not honor locks that it encounters, and it won’t lock anything that it touches. This may result in bad things happening, such as “dirty reads” (reads containing data that hasn’t been committed to the database yet). On the other hand, in some cases the performance gain may be worth the possibility of retrieving bad data. For example, if you wanted to retrieve aggregate values calculated from half a million rows of data, it probably wouldn’t matter too much if one of those rows was being written to by another transaction during the calculation. READ_COMMITTED, the default value, means that the transaction will honor any locks that it encounters, and that it will place locks o
