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Update FAQ_DEV.

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Bruce Momjian
2000-11-04 17:09:24 +00:00
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@ -26,6 +26,7 @@
10) What is elog()?
11) What is configure all about?
12) How do I add a new port?
13) What is CommandCounterIncrement()?
_________________________________________________________________
1) What tools are available for developers?
@ -414,3 +415,15 @@ c-mode)
src/include/storage/s_lock.h for your CPU. There is also a
src/makefiles directory for port-specific Makefile handling. There is
a backend/port directory if you need special files for your OS.
13) What is CommandCounterIncrement()?
Normally, transactions can not see the rows they modify. This allows
UPDATE foo SET x = x + 1 to work correctly.
However, there are cases where a transactions needs to see rows
affected in previous parts of the transaction. This is accomplished
using a Command Counter. Incrementing the counter allows transactions
to be broken into pieces so each piece can see rows modified by
previous pieces. CommandCounterIncrement() increments the Command
Counter, creating a new piece of the transaction.