Toad compile with debug

"I do not want to see bug icon near my PL/SQL procedures."

If this is the case, you must go to session menu and select "toggle compiling with debug". This changes the default behaviour of compiling. And you will not see bug near your procedures in the LHS. Also note that following excerpts from TOAD help topics:

Debugger Overview

"Compiling with debug provides the information Toad needs to navigate the code using the Debugger."

Minimum Oracle Database Requirements

"For all databases, you must have the Oracle Probe API v2.0 or later installed in order to debug PL/SQL using Toad."

When did Optimizer use index FFS in queries having Max(datetime)?

Assume a Table MYTABLEA1, having date type column for example datetime:

select max(datetime) from MYCHEMA.MYTABLEA1;

Row count: 1384

 

Plan
SELECT STATEMENT CHOOSE
	2 SORT AGGREGATE
		1 TABLE ACCESS FULL MYCHEMA.MYTABLEA1

 

select max(datetime) from MYCHEMA.MYTABLEA2;

Row count: 8139221

Plan
SELECT STATEMENT CHOOSE Cost: 442,815 Bytes: 8 Cardinality: 1
	3 SORT AGGREGATE Bytes: 8 Cardinality: 1
		2 PARTITION RANGE ALL Partition #: 2 Partitions accessed #1 - #26
			1 INDEX FULL SCAN (MIN/MAX) NON-UNIQUE MYCHEMA.MYTABLEA2 Cost: 442,815 Bytes: 2.491.053.600 Cardinality: 311.381.700 Partition #: 2 Partitions accessed #1 - #26

 

I quoted folowing from Julian.

The indexed columns must have a NOT NULL constraint

The table does not need to be analysed

http://www.juliandyke.com/Optimisation/Operations/IndexFullScanMinMax.html