![]() My ONE BIG recommendation - Isolate the table into its own database to avoid issues when performing the exchange as it needs a DBD lock to complete. Having worked with CLONE tables for sometime, and got burnt by this one. ![]() Enhancements were need to handle Temporal and Archive tables better. FETCH FIRST n ROWS should be used heavily in online or any application that will not Fetch the entire result set. We have predicate push down to each leg, ORDER BY push down to each leg with any FETCH FIRST n ROWS ONLY, with final Sort doing a merge of the sort results. Optimizer team in V12 has given us some enhancements. Queries that UNION are not necessarily as much of an access path problem as they used to be. I had thought of the Clone table with EXCHANGE as an option but not necessarily a good one, as you say. There are many SQL features that need to be used sparingly if at all.įor switching between two tables I quite often see application SQL that has to UNION the two tables and use a switch subquery predicate to decide which of them will actually be queried to find rows. Sorry, we don't need to make serious mistakes at design time. Roger Miller used to say "Don't ask us how it works, tell us your problem, and we will tell you how to fix it." Ha ha, a joke I guess. We therefore need to understand how it works, somewhat. I always say that SQL gives us a lot of rope to hang ourselves, if we don't use it wisely. So a Daily EXCHANGE to switch between 2 tables might not be a great idea, unless have a quiet time. It is quite evident that Exchange is DDL rather than DML to me, so updating the DBD is fairly obvious, and many DDL operations could be risky for contention in operational systems. ![]() I was just adjusting queries on Catalog to Cater for Clone table RTS Stats. If I understood I might recommend against using R.I. Makes it harder to create Indexes (even when Not Unique Defer Yes), without problems, and could interfere with an EXCHANGE Clone too. ![]() operations can lock the DBD, even if is a share lock. Yet I was expecting an answer of something moderately obvious, but just was eluding me.ĭBD locks are always an annoying thing to me, except for obviously DDL has to update it. This is maybe the first time, at least in near memory, I ever got a quick and definitive answer to a question that was baffling me. I expected joins to match things rather than deduce by absence or inference that the other instance must be the Clone. I did not check SYSTABLESPACE again after my Exchange Tables to see that indeed its instance number had switched from 1 to 2. Subject: RE: Clone Table RTS Stats Question. So the RTS supposedly allows space to be monitored on each of 2 tables separately, but perhaps not really, and we just have to add them together?Īre there other situations where 2 instances will both be valid, unrelated to Clones? Initially Clone is likely to be INSTANCE = 2, but after Exchange of data, it is Instance 1, and original table is Instance 2. So how to tell which RTS Instance is the Clone? I could not see anything in the DB2 Catalog to specify it. It can have two entries in SYSTABLESPACESTATS being instance 1 and instance 2, yet SYSTABLESPACE and SYSTABLEPART have one row each (SYSTABLESPACE has INSTANCE=1 only). Geschäftsführung: Gerhard Schubert, Ulf HeinrichĪ Clone Table lives in same UTS as the original table. I simply join the INSTANCE in SYSTABLESPACE to the INSTANCE in the RTS and you are done! As this is the "active" version of the data and obviously, the "other" instance is the "clone" version. Description: WiseMemoryOptimzer. The process known as Wise Memory Optimizer belongs to software Wise Memory Optimizer or Wise Care (version 365) by. The INSTANCE 2 in the above list were all created by the WiseMemoryOptimzer.exe file information WiseMemoryOptimzer.exe process in Windows Task Manager. Technical Details and System Requirements Perfectly Compatible with Almost All Windows Versions.Automatic Tune-up and Optimization of RAM.Free Up And Tune Up Memory Taken Up By Useless Applications.Moreover, you can enable automatic optimization mode when the free PC memory goes below a value that you can specify and make it run even when the CPU is idle and adjust the amount of memory you want to free up. It helps you free up and tune up the physical memory taken up by some useless applications to boost PC performance. It is straightforward to use for both novices and experts alike. It can execute its tasks following your settings and the physical truth of your computer. This program helps you free up and tune up the physical memory taken up by some useless applications to enhance PC performance. You can also FREE download Universal Extractor. It is used to defrag memory and free up memory with one click easily. Free Download Wise Memory Optimizer 4 full version standalone offline installer for Windows.
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