[ADMIN] SQL preprocessor output

Hi, I would like to know where the query plan build by a sql preprocessor is saved in PostgreSQL. database and how can I show their properties like the date it was build, if it is still valid and so on! Thanks in advance! Do you Yahoo!? New and Improved Yahoo! Mail - 100MB free storage!

[ADMIN] Vacuum x Vacuum full

I would like to know ifspace disk is free to the Operational Systemduring a standard vacuum (without the full option)? I found in section "21.1.1 Recovering disk space" of Postgresql 7.4.2 manual something about it. "The standard form of VACUUM is best used with the goal of maintaining a fairly

[ADMIN] UNDO

Hi, In 7.4 manual is written than UNDO is not implemented. What it really means? When should PostgreSQL do an UNDO? Are not all data only written to disk when it is committed? Why should Postgresql do an undo? Thanks in advance!