When you add a segment to table with our drivers there is a representation of those in the backend (MS SQL, Oracle, MySQL and PostgreSQL).
This is common list of assumptions we have for all drivers:
1. Indexed columns are created as NOT NULL and should have a default value assigned to.
2. Tables are created with the table names with uppercase letters in Flex2SQL, ORAFlex and DB2Flex.
MySQL has two different types of licensing agreements.
Open Source license (GNU) and the other more applicable to developers is their Commercial license. Below are excerpts from the MySQL documentation.
NOTE: Since Mertech’s drivers are not open source; anyone using our drivers along with MySQL must purchase a Commercial license.
This example returns user information from MySQL:
StatsPack is an Oracle package for monitoring performance statistics.
Rollback segment size refers to needing an accurate minimum number of bytes required by the rollback segment for any single given transaction or for the most important of these. There are differences between the kind of transactions (INSERTS, UPDATES and DELETES).
Oracle 11g has a new hint telling data to persist in cache for x number of minutes.
The syntax is:
If a table or index becomes fragmented (not continuous on disk) performance can decrease. You can see which objects have over 10 extents with:
A lot of developers use embedded SQL, or other tools to access their data. If a query is not optimized it can cause problems.
In Oracle 11g we have the memory_max_target parameter which governs the total maximum RAM for both the PGA and SGA regions and the new memory_target parameter which governs the existing sizes. This allows RAM to be de-allocated from the SGA and transferred to the PGA.