Before I forget, I want to write a few words on this. It's my feeling, one might say "gut feeling" about the technology or technological world. Sometimes, what it seems, may not be the case for a product. In my opinion, people actually buy "trust" with money! It is fair as long as that meets the demands.
For replication, the product we chose, we had been told that the product were being used by many fortune 500 companies and wall street shops were really happy with the product.
The reality is, we found a number of problems time to time, which we did never expect from such a "high profile" product. It seems that they never had an extensive user like us or they were lagging for testing resources, sounds funny though!
* During the transition phase, one special feature of the product swapped our data between two servers and the databases got out of sync. It was really really hard to understand which data was more correct. To correct the problem, I had to go through about each and every 7000 records - one by one :-(
* Initially, the LOB replications were problematic - after replication, it inserted invalid and empty spaces in between each and every characters on destination database. We could not believe this!
* Again, after 2 months, I discovered another replication problem with CLOB data type. At destination server, after replication, some character got truncated. This problem specially happens with Multibyte character set. We reported the problem but "they" did not understand what was happening. On this issue, I had to spend 3/4 days to analyze, reproduce and pin-point the problem and I described why and how this is happening with a big explanation like a detective - the company were not able to find the cause of the problem initially.
* After few months, again discovered problem with BLOB replication. The product generates some internal files after capturing changes. For some bug in their product, what I saw is, for 20 MB data size in BLOB field, the product were generating internal files of size more than 20 GB! So, one night we caught for out of disk space!
It seems that we were doing extensive testing for their product and coming up with bugs to fix.
Well, I am not going to tell you which third party replication product we are using. But what I want to point out is - one should test any third party product (my recommendation) if they think that they are doing something vary important for their customers. We can't always rely on what other says or how big the product profile is!
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