Просторы интернета
GET POST PUT DELETE HEAD OPTIONS Another REST sample is now over. This is [...]
When starting the SOA server, the following exception may occur.
log is opened. All server side log events will be written to this file.> cation for user weblogic denied weblogic.security.SecurityInitializationException: Authentication for user weblogic denied at weblogic.security.service.CommonSecurityServiceManagerDelegateImpl.doBootAuthorization(CommonSecurityServiceM at weblogic.security.service.CommonSecurityServiceManagerDelegateImpl.initialize(CommonSecurityServiceManagerDel [...]
I faced the problem that it took a long time to execute select in DB Adapter. There were three tables that contained a large amount of data and contained many columns, and these tables were being handled by the DB Adapter.
The database side configured a primary key / foreign key [...]
Test data:
create table t_str as select round(dbms_random.value(1e10,9e10)) str from dual connect by level select min(fstr) res2 2 from t_str t 3 cross apply ( 4 select listagg(c) within group (order by 1) fstr 5 [...]Simple example: tracefiles for the last 5 days:
select fc.* from v$diag_trace_file f join v$diag_trace_file_contents fc on f.adr_home=fc.adr_home and f.trace_filename=fc.trace_filename where f.modify_time >= systimestamp - interval'5' minute and fc.timestamp [...]I know this syntax for a long time, since when lateral() was not documented yet, but recently I found a bug: the following query successfully returns 1 row:
with a as (select level a from dual connect by level [...]PL/SQL functions in Oracle can be tagged with a DETERMINISTIC clause, to indicate that the function will always produce the same output for a given input and will have no side effects.
A little elaboration is in order here.
1. …will always produces the [...]Recently I got a question: why CBO chooses “FIXED TABLE FULL TABLE” scan instead of “FIXED INDEX” in case of a join to flashback_transaction_query view with the predicate “q.xid = a.versions_xid”:
select versions_xid, versions_startscn, versions_starttime, versions_endscn, versions_endtime, --scn_to_timestamp, to_char(a.classification), a.* from vms.advisory_arch_20190624 versions between [...]Some time ago there was a question on the sql.ru about splitting validity periods for gym cards to enabled and blocked periods:
-- we have a table with gym cards (card id, validity period: from/to) CREATE TABLE cards(id_card NUMBER, num_card VARCHAR2(100), dt_from DATE, dt_to DATE); -- periods when cards were blocked (record id, [...]You may know that table() (kokbf$ collection functions), xmltable and json_table functions block Join-Predicate PushDown(JPPD).
Simple example:
You can see that JPPD works fine in case of global temporary tables and, obviously, the first workaround is to [...]
Today I wanted to give a link to the description of v$sql_hint.target_level to show that no_parallel can be specified for statement or object, and though it's pretty obvious, but surprisingly I haven't found any articles or posts about it, so this short post describes it.
v$sql_hint.target_level is a bitset, where
1st bit [...]
Sometimes it might be useful to analyze top time-consuming filter and access predicates from ASH, especially in cases when db load is spread evenly enough by different queries and top segments doesn't show anything special, except usual things like “some tables are requested more often than others”.
Of course, we can [...]
It is quite normal for Oracle database objects to become INVALID, especially when a dependency chain is broken. This articles takes a closer look at:
typical reasons why Oracle objects become INVALID how to identify INVALID objects [...]Consider a PL/SQL stored procedure that handles a heavy transaction. The procedure is extremely slow – when executed from a UI, the application hangs for minutes. On analysis it is found that the procedure is performing a complex series [...]
When UTL_HTTP web service calls nicely return 2xx status codes, all is well with the world. Things get tricky when a web service call encounters an error and sends back a non-2xx response. [...]