Wednesday 23 January 2013

Some notes on materialized views

Few loosely notes on materialized views.

It is possible to build a mview on a pre-built table. I like this feature mainly because one is able to drop such view and recreate it with slightly changed definition, while the data is preserved, which is very valuable especially when dealing with large source tables.

Another observation is that sometimes the casting to right types is necessary. We met several times the situation when on Linux some mview definition worked properly while on AIX it failed due to not strong type casting, when the solution was to use CAST with precision to type and length (usually the problem core was longer VARCHAR2 than expected).

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