For me , going via ANSI route is lot more text than the Oracle Syntax. Wonder , if Oracle could give out a syntax for Full Outer Join and Partition Outer Join ( in Oracle Syntax) .

Even If I write

Too many people want answers in black and white – subtle shades of grey are not allowed in the Oracle world. (Okay, tongue slightly in cheek, there – occasionally a little dramatic effect is allowable, especially when the original source is placed in front of you so that you can see the actual wording.)

But here we are: I say “I’m not keen on…”, “.. reason for disliking … ” and this is reported as “Jonathan hates ANSI”.

Shades of Dilbert !

I wonder how difficult is finding how SQL statement looked like after transformation (and before optimization) from 10053 trace, even in 11gR2. I’m using 10gR2 most of time, so I knew it is difficult in 10g, but didn’t know it is still so painful in 11g. You have made great job Jonathan, again.

There is mentioned some kind of “UNPARSED QUERY”, in the trace, but not the final version

Join Elimination (JE)
*************************
SQL:******* UNPARSED QUERY IS *******

SELECT "Q1"."T1_I1" "T1_I1", "Q1"."T1_I2" "T1_I2", "Q1"."T1_D1" "T1_D1",
       "Q1"."T2_I1" "T2_I1", "Q1"."T2_I2" "T2_I2", "Q1"."T2_TS" "T2_TS",
       "Q2"."T3_I1" "T3_I1", "Q2"."T3_I2" "T3_I2", "Q2"."T3_TSTZ" "T3_TSTZ",
       "Q2"."T4_I1" "T4_I1", "Q2"."T4_I2" "T4_I2"
  FROM (SELECT /*+ NO_MERGE QB_NAME ("Q1BLOCK") */
               "from$_subquery$_003"."T1_I1_0" "T1_I1",
               "from$_subquery$_003"."T1_I2_1" "T1_I2",
               "from$_subquery$_003"."T1_D1_2" "T1_D1",
               "from$_subquery$_003"."T2_I1_3" "T2_I1",
               "from$_subquery$_003"."T2_I2_4" "T2_I2",
               "from$_subquery$_003"."T2_TS_5" "T2_TS"
          FROM (SELECT "T1"."T1_I1" "T1_I1_0", "T1"."T1_I2" "T1_I2_1",
                       "T1"."T1_D1" "T1_D1_2", "T2"."T2_I1" "T2_I1_3",
                       "T2"."T2_I2" "T2_I2_4", "T2"."T2_TS" "T2_TS_5"
                  FROM "SYS"."T1" "T1", "SYS"."T2" "T2"
                 WHERE "T1"."T1_I1" = "T2"."T2_I1" AND "T1"."T1_I1" < 10) "from$_subquery$_003") "Q1",
       (SELECT /*+ NO_MERGE QB_NAME ("Q2BLOCK") */
               "from$_subquery$_006"."T3_I1_0" "T3_I1",
               "from$_subquery$_006"."T3_I2_1" "T3_I2",
               "from$_subquery$_006"."T3_TSTZ_2" "T3_TSTZ",
               "from$_subquery$_006"."T4_I1_3" "T4_I1",
               "from$_subquery$_006"."T4_I2_4" "T4_I2"
          FROM (SELECT "T3"."T3_I1" "T3_I1_0", "T3"."T3_I2" "T3_I2_1",
                       "T3"."T3_TSTZ" "T3_TSTZ_2", "T4"."T4_I1" "T4_I1_3",
                       "T4"."T4_I2" "T4_I2_4"
                  FROM "SYS"."T3" "T3", "SYS"."T4" "T4"
                 WHERE "T3"."T3_I1" = "T4"."T4_I1" AND "T3"."T3_I1" < 10) "from$_subquery$_006") "Q2"
 WHERE "Q1"."T1_I1" + "Q1"."T2_I1" = "Q2"."T3_I1" + "Q2"."T4_I1"

BTW I suggest you have ommited one little detail, just one alias “from$_subquery$_009″. But is has no impact on using hints referencing query block names.

.
.
.

            AND T3.T3_I1 < 10
            )   from$_subquery$_006
        )   Q2
    WHERE
        Q1.T1_I1 + Q1.T2_I1 = Q2.T3_I1 + Q2.T4_I1
    ) from$_subquery$_009
;

“Old style is short and sweet and perfect.
Ansi dumbed it down, that’s the bottom line.
And for people who’ve been developing for sometime,
It’s wholly unnecessary.”

I use whichever syntax is the house style when I’m on assignment; but even though ANSI is the “strategic” choice, I will suggest to people that they may need to think about rewriting complex statements in Oracle syntax if they need to hint them into execution paths the optimizer can’t find.