tune my database! mehr oracle sql performance über sqlhc - yann neuhaus, nicolas jardot, dbi...

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dbi services

SQL Health Check

www.dbi-services.com 1 08.11.2012

Yann Neuhaus

CEO – Region Manager Basel Area

Mobile +41 79 963 27 20

[email protected]

www.dbi-services.com

Nicolas Jardot

Consultant

Mobile +41 79 835 02 95

[email protected]


mailto:[email protected]




http://www.dbi-services.com/










Agenda Agenda

SQL Health Check

Agenda

i. Introduction

ii. Concept

iii. Usage

iv. Case study



Many parameters may influence SQL executions

CBO settings, Objects statistics,…

Tuning requires to check and analyze these parameters

Cloud Control allows to monitor SQLs to find which one is the more consuming

SQL Health Check

Introduction



SQL Health Check

Introduction – Highlight


SQLHC

is a script from Oracle Download at My Oracle Support, note 1366133.1

dbi services advices to regularly check if new version is available

creates a report on an SQL statement

focus only on one statement

is available for free SQHC is not dependent of Tuning/Diagnostic Pack license

does not require installation


SQL Health Check

Introduction – Highlight



Agenda Agenda

SQL Health Check

Agenda

i. Introduction

ii. Concept

iii. Usage

iv. Case study



How SQLHC script works?

Quickly get a report of the execution environment

Require SYS account or DBA role

Can be run locally of from distant client

Does not create objects in the database

SQL Health Check

Concept



What is checked?

CBO settings

Objects statistics

Instance parameters

Execution plans

SQL Health Check

Concept



SQL Health Check

Concept



Instance parameters

SQL Health Check

Concept



SQL Health Check

Concept



Agenda Agenda

SQL Health Check

Agenda

i. Introduction

ii. Concept

iii. Usage

iv. Case study



Run script from SQL Plus

License level

T: Tuning Pack

D: Diagnostic Pack

N: None

The output contains several files

SQL Health Check

Usage


SQL> @sqlhc.sql [ T | D | N ] sql_id

*_1_health_check.html

*_2_diagnostics.html

*_3_execution_plans.html

[*_4_sql_detail.html]

[*_5_sql_monitor.zip]

[*_6_10053_trace_from_cursor.trc]


Agenda Agenda

Edition Based Redefinition

Agenda

i. Introduction

ii. Concept

iii. Usage

iv. Case study



Human Resource Application

SQL Health Check

Case study



Full table scan on both tables EMPLOYEES and JOBS

Existing index IDX_JOB_TITLE on column present in the where clause not used

Why index is not used?

Bad/missing statistics or histograms

Instance parameters

Bad selectivity

…

Let’s focus on SQLHC report

SQL Health Check

Case study - Methodology



dbi services

Any Questions? Please Do Ask!


„We look forward to working with you!“

Yann Neuhaus

CEO – Region Manager Basel Area

Mobile +41 79 963 27 20

[email protected]


Nicolas Jardot

Consultant

Mobile +41 79 835 02 95

[email protected]















tune my database! mehr oracle sql performance über sqlhc - yann neuhaus, nicolas jardot, dbi...

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