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Index suggestion from the access advisor

Test case : create table t(x varchar2(8) primary key,   y varchar2(30)); insert into t(x,y) select   to_char(rownum,’FM00000000′),   object_name from all_objects where rownum<1e4; commit; exec dbms_stats.gather_table_stats(user,’T’) One user wants to filter on x but does not do the casting properly SQL> select * from t where x=00000001; X        Y                             ——– —————————— 00000001 CON$ He received the expected data. […]

SPARC Supercluster

Oracle buys Sun was an exciting accouncement 20 months ago. What did change in the Solaris/Oracle Database world? First, Oracle delivered Exadata on Sun Hardware (x86_64). Second, they delivered Exadata on Sun Solaris Operating System (x86_64). But now, they announced a combination of software and hardware that will run Oracle database faster than anything ever [...]

connect by and recursive with (part 2)

According to the doc
The subquery_factoring_clause now supports recursive subquery
factoring (recursive WITH), which lets you query hierarchical data.
This feature is more powerful than CONNECT BY in that it
provides depth-first search and breadth-first search, and supports
multiple recursive branches. A new search_clause and cycle_clause
let you specify an ordering for the rows and mark cycles in the
recursion
As written there [...]