.. -*- coding: utf-8; -*-

.. include:: HEADER.rst

==================

 Oracle database.

==================

.. contents::

Oracle database development environment.

========================================

  http://en.wikipedia.org/wiki/Oracle_SQL_Developer

                Integrated development environment (IDE) for working with

                SQL/PLSql in Oracle databases.

  http://en.wikipedia.org/wiki/SQL*Plus

                An Oracle database client that can run SQL and PL/SQL commands

                and display their results.

  http://en.wikipedia.org/wiki/Oracle_Forms

                Is a software product for creating screens that interact with an

                Oracle database. It has an IDE including an object navigator,

                property sheet and code editor that uses PL/SQL.

  http://en.wikipedia.org/wiki/Oracle_JDeveloper

                JDeveloper is a freeware IDE supplied by Oracle Corporation. It

                offers features for development in Java, XML, SQL and PL/SQL,

                HTML, JavaScript, BPEL and PHP.

  http://en.wikipedia.org/wiki/Oracle_Reports

                Oracle Reports is a tool for developing reports against data

                stored in an Oracle database.

Useful PL/SQL stub.

===================

::

  set serveroutput on;

  set autotrace on statistics;

  set timing on;

  declare

  begin

    null;

  end;

  /

Информация о таблицах в БД Oracle.

==================================

Список таблиц::

  select * from user_tables;

Занимаемый размер таблиц и индексов::

  select segment_name, segment_type, sum(bytes) from user_extents

    group by segment_name, segment_type order by sum(bytes);

  select sum(bytes) from user_extents;

Список индексов по таблицам::

  select * from user_indexes order by table_name;

Список размеров индексов по таблицам::

  select index_name, table_name, sum(user_extents.bytes) as bytes from user_indexes

    left outer join user_extents on user_extents.segment_name = table_name

    group by index_name, table_name

    order by table_name;

Список ограничений::

  select * from user_constraints;

Используемое пространство таблиц::

  select distinct tablespace_name from user_tables;

Profiling.

==========

Timing info about last queries::

  select LAST_LOAD_TIME, ELAPSED_TIME, MODULE, SQL_TEXT elasped from v$sql

    order by LAST_LOAD_TIME desc

Improved version of above code::

  column LAST_LOAD_TIME format a20;

  column TIME format a20;

  column MODULE format a10;

  column SQL_TEXT format a60;

  set autotrace off;

  set timing off;

  select * from (

    select LAST_LOAD_TIME, to_char(ELAPSED_TIME/1000, '999,999,999.000') || ' ms' as TIME, MODULE, SQL_TEXT from SYS."V_\$SQL"

      where SQL_TEXT like '%BATCH_BRANCHES%'

      order by LAST_LOAD_TIME desc

    ) where ROWNUM <= 5;

In SQL/Plus::

  SET TIMING ON;

  -- do stuff

  SET TIMING OFF;

or::

  set serveroutput on

  variable n number

  exec :n := dbms_utility.get_time;

  select ......

  exec dbms_output.put_line( (dbms_utility.get_time-:n)/100) || ' seconds....' );

See:

  http://docs.oracle.com/cd/B19306_01/server.102/b14237/dynviews_2113.htm

                $SQL lists statistics on shared SQL area without the GROUP BY

                clause.

Last table modification time.

=============================

::

  select max(scn_to_timestamp(ora_rowscn)) from TBL;

  select timestamp from all_tab_modifications where table_owner = 'OWNER';

  select timestamp from all_tab_modifications where table_name = 'TABLE';

List of Oracle Reserved Words.

==============================

 * http://docs.oracle.com/cd/B19306_01/em.102/b40103/app_oracle_reserved_words.htm

Adjust date format.

===================

::

  column parameter format a32;

  column value format a32;

  select parameter, value from v$nls_parameters;

  alter session set NLS_DATE_FORMAT = 'yyyy-mm-dd HH:MI:SS';

  alter session set NLS_TIMESTAMP_FORMAT = 'MI:SS.FF6';

  alter session set NLS_TIME_FORMAT = 'HH24:MI:SS.FF6';

  select sysdate from dual;