Blogs on the databases of members of our social network of programmers and system administrators on various topics. First of all, we pay attention to Oracle Database and MySQL databases. We also consider the basics of databases: theory and design methods, DBMS development, SQL language (and its extension for Oracle - PL/SQL). In our blogs we explain the basics of database administration, programming applications for beginners, and share the secrets of the solution complex problems. Share your knowledge, ask questions, publish ready-made solutions and recipes! Help newcomers and show your professionalism! Headhunters don't sleep!

Let's say you need to hire a web developer who has worked with Angular. What do you think such a specialist should know? He must understand the architecture, components and concepts of Angular applications, but this is not enough. The following relatively long list outlines the languages ​​and tools used by professional Angular developers. Not all of them are needed to develop and deploy specific applications, but an Angular programmer should potentially be competent in using these tools.

Is it necessary to use frameworks? No, you can write the client side of web applications in pure JavaScript. In this case, there is no need to learn something new, knowledge is enough JavaScript language. Eliminating frameworks will lead to difficulties maintaining cross-browser compatibility, as well as longer development cycles. Frameworks allow you to fully control the architecture, design patterns, and code styles of your application. Most modern web applications are written using a combination of several frameworks and libraries.

Problem

You have an app that collects anonymous app usage data, so you have a responsibility to inform users about this when they first launch the app.

Solution

Store General settings, storing their values ​​only once. Every time the application starts, it checks these values ​​in the settings.

Problem

Developers often want to track their applications in terms of features used by users. How can you determine which feature is used most by your app's users?

Solution

Use Google Analytics to track an application based on certain criteria, similar to Google Analytics' website tracking.

Problem

You want to create a splash screen that appears when an Android application loads.

Solution

You can create a splash screen as an Activity object or as a dialog box. Since its purpose is achieved within a few seconds, it can be removed after a short period of time or by pressing a button on the splash screen.

Problem

You want to detect the battery level on an Android device so that you can notify the user when the battery level drops below a certain threshold, thus avoiding unexpected surprises.

Problem

When the user rotates the device, Android system usually destroys and recreates the current activity. You want to save some data in this loop, but all the fields in your activity will be lost.

There are several approaches. If all your data contains primitive types, consists of String objects, or is Serializable objects, you can save it using the onSavelnstanceState() method in the passed Bundle class object.

How to access global data from an Android app

Details Category: Programming Published: March 05, 2019 Views: 258 September 23, 2019 (Moscow) November 25, 2019 (Moscow)

Price:

RUB 38,745 10% discount until 03/17/2019

RUB 34,870

For proper use Oracle must have good understanding SQL language. Well " Oracle. Programming in SQL, PL/SQL and Java"reveals the full range of capabilities of the SQL language in Oracle and a number of aspects of non-obvious features of building standard database designs.

• PL/SQL - procedural language, developed by Oracle for writing subroutines stored in the database. PL/SQL provides a common framework for procedural programming in both client-side and server-side applications, including server-based routines, packages, and database triggers.
• Java - object language, which can be used to work with Oracle in a variety of configurations, including, thanks to Oracle's built-in Java engine, as a second language for stored procedures. Java is independent of specific platforms and can serve as an effective means of integrating the Oracle database with other applications, including those on the Internet.

The course is accompanied by practical exercises to reinforce understanding basic concepts and master basic technical techniques of programming in SQL, PL/SQL and Java.

Upon completion of the course Students get the opportunity to independently program Oracle in these three languages ​​to solve application development problems in a client-server architecture and in a three-tier architecture, as well as database administration tasks.

The main difference between this course and a number of others with similar topics is that the goal is to teach specific students how to actually work with Oracle in these languages, and not to read a formal program prepared by a third party.

The course is intended for developers, programmers and database administrators. Students must have a good level of computer literacy and programming experience.

Knowledge is given according to the following versions:

• Oracle Database 8i
• Oracle Database 9i
• Oracle Database 10g
• Oracle Database 11g
• Oracle Database 12c

Course program "Oracle. Programming in SQL, PL/SQL and Java"

Introduction to Oracle SQL

1. Basic concepts

• Databases and relational model
• Database
• Relational Approach to Data Modeling
• Implementation relational DBMS
  Other approaches to data modeling and other types of DBMS
• What is SQL?
• History and standards
• Oracle dialect SQL
• PL/SQL

2. SQL*Plus and entering sentences in SQL

3. Example of a database "schema"

4. Creating, deleting tables and changing the structure

• CREATE TABLE clause
• Column Data Types
• Clarifications in column descriptions
• NOT NULL indication
• Default values
• Checking CHECK of values ​​entering the table
• Creating tables based on the results of a database query
• Naming tables and columns
• Virtual Columns
• Removing tables
• Changing the table structure
• Logical and technical features of deleting a column
• Using synonyms to name tables
• Renaming
• Reference information about tables in the database

5. Basic Elements of DML Sentences: Expressions

• Immediate data values ​​(literals)
• Numeric values
• Lines of text
• Moments and time intervals
• "System Variables"
• Numeric Expressions
• Expressions over lines of text
• Expressions over the "point in time" type
• Functions
• Scalar functions
• CASE expressions
• Scalar query
• Conditional Expressions
• Special notes on missing values ​​in expressions

6. Data sampling

• SELECT clause phrases
• General rules for constructing a SELECT clause
• How the SELECT clause is processed
• SELECT clause example 1
• Example 2 SELECT clause
• Logical integrity of SELECT clause processing
• FROM clause of the SELECT clause
• Options for specifying a column
• Columns from different tables
• Using aliases in a request
• Subquery as a data source
• Special case for request-connection
• WHERE clause of SELECT clause
• General algorithm for processing the WHERE phrase
• Comparison operators to obtain a conditional expression
• AND, OR and NOT connectives for combining conditional expressions
• Conditional operator IS
• Conditional LIKE operator
• Conditional operator BETWEEN
• Conditional IN operator with explicitly enumerable set
• Conditional operator IN with a set obtained from the database
• Comparison conditions with a subquery
• Specifying ANY and ALL to compare against elements of a value set
• Conditional operator EXISTS
• SELECT clause and functions in the SELECT clause
• Shorthand for group selection of columns
• Expressions in the SELECT clause
• Subqueries in the SELECT clause
• Clarification DISTINCT
• Features of the behavior of standard aggregate functions in the SELECT clause
• Naming columns in query results
• System function ("variable") ROWNUM and features of its use
• Analytical functions
• Expression of type reference to cursor
• ORDER BY clause of the SELECT clause
• The simplest sorting
• Order by expression value
• Specifying a column number
• Binary and "language" string ordering
• Features of handling missing values ​​(NULL)
• GROUP BY and HAVING clauses of the SELECT clause
• An example of working out the phrase GROUP BY ... HAVING
• Missing value in grouping expression
• Other examples
• Specifying ROLLUP, CUBE and GROUPING SETS in the GROUP BY clause
• CONNECT BY clause of the SELECT clause
• Special system functions in clauses with CONNECT BY
• Ordering the result
• WITH clause pre-formulation of subqueries
• Combining SELECT Clauses
• Combining with the UNION operator
• Combining with the INTERSECT operator
• Combining with the MINUS operator
• Subqueries
• Join operation in SELECT clause
• Types of connections
• New syntax in version 9
• Features of the connection operation

7. Updating data in tables

• Adding New Rows
• Explicitly adding a row
• Adding Rows Retrieved by a Subquery
• Adding to multiple tables with one statement
• Changing existing field values
• Using default values ​​in INSERT and UPDATE
• Removing rows from a table
• Selective deletion
• Complete removal option
• Combining UPDATE, INSERT and DELETE in one statement
• Logical integrity of table data update operators and response to errors
• Reaction to errors during execution
• Recording changes in the database
• System change number information for a line
• Speeding up COMMIT execution

8. Quickly access past data values

• Reading old table row values
• Recovering tables and data from previously deleted tables

9. Circuit integrity constraints

• Varieties circuit restrictions integrity
• NOT NULL constraint
• Primary keys
• Uniqueness of values ​​in columns
• Foreign keys
• Additional condition for value in string field
• Additional condition that links values ​​in multiple fields in a row
• Adding a restriction if there are violations
• Suspending schema constraint checking within a transaction
• Disable or enable circuit integrity constraints
• Technology for enabling and disabling circuit integrity constraints
• More complex integrity rules

10. Virtual tables (derived, displayed: views)

• Basic ("core") and virtual tables
• Updating virtual tables
• Limitations of direct data modification via virtual tables
• Prohibiting immediate updates
• Reducing the possibility of immediate updates
• Virtual tables with data storage
• Features of named virtual tables
• Unnamed virtual tables without data storage

11. Non-scalar types for “complex” data in Oracle

• Stored objects
• Simple example
• Using Object Properties and Methods
• Using Object References
• Collections
• Nested tables
• VARRAY arrays
• XMLTYPE
• Simple example
• XMLTYPE data tables
• Converting tabular data to XMLTYPE
• Type ANYDATA

12. Auxiliary types of stored objects

• Unique numbers generator
• Operating system directory
• Tables with temporary storage data
• Link to another database
• Subroutines
• Indexes
• Indexes for checking circuit integrity constraints
• Tables with external data storage

13. Some notes on optimizing SQL statements

14. Transactions and locks

• Transactions in Oracle
• Examples of data locking by transactions
• Types of locks
• Implicit locks on DML operations
• Impact of Foreign Keys
• Explicit table locking (TM type) with the LOCK command
• Explicitly locking individual table rows
• An undocumented form of group blocking
• Blocking by DDL clauses

15. Users (schemas) and additional means of restricting access to data

16. Tables of the system catalog (dictionary-reference)

18. Embedded SQL

• Some examples of query writing

19. Issue employees in accordance with a higher (lower) salary

• Question to the database
• "Obvious" but wrong solution
• The right decisions
• Top-N solution (since version 8.1.5)
• Solution using analytical ranking functions

20. Reformulating the query with HAVING

22. NOT Conditional Trap

23. Trap in NOT IN (S)

Introduction to PL/SQL

1. Basic concepts

• Place of PL/SQL in Oracle architecture
• General structure of a PL/SQL program

2. Basic data types and structures

• Scalar variables
• Numeric types
• String types
• Time points and intervals
• Boolean variables
• LOB types
• Declaring Variables and Constants
• Posts
• Declaring entries in a program
• Assignments
• Link to types of data already available
• Custom Subtypes

3. Expressions

4. Main control structures

• Program branching
• IF-THEN offer
• IF-THEN-ELSE clause
• IF-THEN-ELSIF proposal
• CASE offers
• Unconditional transfer of control
• Cycles
• Simple loop
• Counting cycle (FOR)
• Cycle on cursor (FOR)
• WHILE loop
• Simulating a REPEAT UNTIL loop
• Labels in cycles and blocks

5. Subroutines

• Local routines
• Redefining "external" names
• Forward announcements
• Repeating names at the same level (overloading)
• 6. Interaction with the database: static SQL
• Using records instead of (list of) scalars

7. Regulating changes in the database

• Transaction management
• Locks
• Autonomous Transactions

8. Built-in dynamic SQL

• Embedded dynamic SQL statements
• Comparative example of two ways to work with dynamic SQL

9. Using cursors

• Explicit cursors
• Declaring Explicit Cursors
• Opening Explicit Cursors
• Retrieving the result via an explicit cursor
• Closing an explicit cursor
• No restrictions on table changes when the cursor is open
• Attributes for Explicit Cursors
• Some examples of using loops and cursors
• Cursors with table row locking
• SELECT ... FOR UPDATE clause
• Precautions for using locking cursors
• Ability to change the lines selected by the cursor
• Cursor references
• General information
• Example of use for structuring a program
• Implicit cursors

10. Handling exceptions

• Declaring Exceptions
• Processing examples
• Throwing exceptions
• Coverage and distribution
• "Internal" block exceptions
• Using the SQLCODE and SQLERRM Functions

11. Stored procedures and functions

• General syntax
• Options
• Parameter type
• Parameter usage mode
• Default values
• Ways to specify actual values ​​for parameters
• Accessing parameters and local variables in the body of a subroutine
• Instructions for the compiler when creating subroutines
• Stored routines and data access privileges in the database
• Two logics for implementing access privileges to database data
• Features of transferring privileges through roles

12. Trigger procedures

• Creating a trigger procedure
• Disabling trigger procedures
• Trigger procedures for DML category events
• Combined trigger procedures
• Managing transactions in the body of a trigger procedure
• The sequence of trigger procedures when there are several of them
• Trigger procedures INSTEAD OF for inferred tables
• Trigger procedures for DDL events
• Trigger procedures for schema and database level events

13. Packages in PL/SQL

• General package structure
• Accessing package elements
• (Global) package data
• Mutual calls and repetitions of names
• Package initialization
• Pragma SERIALLY_REUSABLE

14. Calling PL/SQL Functions in SQL Statements

• Requirements and restrictions for using user functions in SQL
• Calling functions from packages in SQL
• Resolving Column and Function Name Conflicts
• Table functions in SQL

15. More complex data types: collections

• Type declaration syntax for collections
• Working with associative arrays
• Creating a nested table and VARRAY array in a program
• Adding and removing items in collections
• Multiple actions with collections
• Collection Conversions
• Methods for working with collections in the program
• Examples of using collections in the program
• Privilege
• Serial execution and binding of queries to arrays
• Serial execution of similar operations: FORALL construction
• Binding with arrays: BULK COLLECT INTO construct
• Example for SCOTT circuit
• Using collections in table functions (streaming implementation)
• Simple example
• Use for data conversion

16. Debugging procedures in PL/SQL

• Dictionary tables
• Routine dependencies
• System packages
• Package DBMS_PROFILER
• DBMS_TRACE package
• DBMS_UTILITY package functions
• Package DBMS_DEBUG
• An example of constructing a program operation profile

17. Programming systems for PL/SQL

18. PL/SQL system packages

• Packages STANDARD and DBMS_STANDARD
• Other system packages
• Writing data from a program to a file and back
• Data encryption
• Automatically running jobs in Oracle
• Managing the dynamic placement of objects in the library buffer
• Manipulating large unstructured NULL objects
• Accessing Old Data Values
• Sending messages from a PL/SQL program
• Opportunities for working in PL/SQL with COM Automation
• additional information

• A simple example of separating cursor opening and processing
• More complex example division of work

20. Attributes of trigger procedures at the level of the database schema and events in the DBMS

INTRODUCTION TO ORACLE PROGRAMMING IN JAVA

1. Basic concepts

• Java's Place in Oracle Architecture
• Relationship and relationship between PL/SQL and Java in Oracle

2. Features of Java and the operating environment for Java programs

• Java architecture
• Software components in a Java development environment
• Installing the Java Development Environment
• OS Environment

3. Creating independent programs in Java

• An example of broadcasting and executing a program

4. Creating Java Stored Programs in Oracle

• Additional Oracle DBMS components for working with stored programs in Java
• Limitations on Stored Programs in Java
• Installing, uninstalling and updating JServer/OJVM
• Example of creating a stored Java program
• Building with loadjava
• Creation by SQL statement
• Calling a loaded class
• Working with a reference dictionary
• Organization of reference information
• Viewing Java Elements
• View Sources
• Name conversion
• Features of the embedded JVM
• Interpreter ojvmjava

5. Elements of Java programming

• Language Basics
• Basic language constructs
• Variables
• Operators
• Expressions, clauses and blocks
• Transfer of control
• Objects and simple structures
• Classes and inheritance
• Creating classes
• Mechanics of using a class in a program
• Inheritance
• Interfaces
• Exception Handling
• Some Java Programming Techniques
• GUI
• Groups of objects (collections)
• Streaming input and output
• Parameterization of program operation using property sets
• Object Serializability

6. Interaction with the database via JDBC

• Using JDBC
• JDBC and JDBC drivers
• JDBC Drivers in Oracle
• Installing JDBC drivers for working with Oracle
• Java program to test connectivity via JDBC
• Working with Oracle data from external Java programs
• Accessing the database through a thick OCI driver
• Working with Oracle data from stored Java programs
• Accessing the database through a thick driver (“native”, kprb)
• Accessing the database through a thin driver
• Accessing data from Oracle trigger procedures

7. Additional properties of the JDBC protocol

• Connecting to a DBMS using the DataSource technique
• A simple example of connecting using the DataSource technique
• Example connection using JNDI service
• Connection caching example
• Examples of organizing logical connections
• Changing data in the database and accessing stored routines
• Changing data
• Transaction management
• Accessing stored programs
• Query parameterization
• Using Oracle Data Types
• Improving the efficiency of database calls
• Recurring requests
• Batch execution
• Link from the program to the cursor in the DBMS

8. Interacting with the database via SQLJ

• Simple example program
• Translating and executing a program with SQLJ
• A more complex example: multiple sampling from a database
• Using SQLJ in Java Stored Procedures
• Example with external loading
• Example with internal broadcast

9. Basics of building applications for the web using Java and Oracle

• Client part: working with applets
• An example of broadcasting and executing an applet
• Apache Web Server
• Communication with a web server via HTTP protocol
• General concepts of HTTP messaging
• Organizing a dialogue in HTML
• Working with Java Servlets
• Understanding Java Servlets and Servlet Containers
• Java Servlet Device
• An example of composing a servlet in Java
• Example of calling a servlet
• Example of a servlet accessing a database
• Using the HttpServlet class
• Working with JavaServer Pages
• Example of composing a JSP page
• Example of accessing a JSP page
• Some options for building JSP pages
• Ways to access a database from a JSP page
• MVC model of organizing an application for the web

10. Interaction of application components for the web

• Transferring control of web application components to each other
• Contact us HTML pages to JavaServer pages and servlets
• Transferring control from JavaServer pages
• Transferring control to web components from servlets
• Java abstractions for building a web application
• Request and response
• Scope
• Servlet context
• Predefined JavaServer Page Objects
• Passing web application component data to each other
• Passing data through request parameters
• Passing Data Through Context and JavaBeans Components

11. An example of building a web application using Java and Oracle

• Logon.html page
• Servlet Logon
• LogonError.html page
• Main.jsp page
• Page CompanyData.jsp and class orajava.demos.StuffData
• Servlet Logout
• Broadcasting classes, hosting files, and testing the application
• additional information

12. Example of programming custom JSP markup

• An example of using ready-made markup
• Example of programming your own markup

At the end of the course, a final certification is carried out in the form of a test or based on grades for practical work completed during the training process.

In the modern world it is difficult to do without information technologies and their derivatives - computers, mobile phones, Internet, etc., especially in large companies and government organizations that work with a large number of people, and not just with a couple of VIP clients, as may be the case in a small company. And where there are a large number of counterparties, applicants, etc. - you cannot do without databases necessary for processing information. Naturally, the days of ledgers and cards, remembered by many from libraries, are long gone; today they are used personal computers and electronic databases.

Today it is impossible to imagine the work of the largest companies, banks or government organizations without the use of databases and tools Business Intelligence. Databases allow us to store and access large volumes information and database management system(DBMS) - manage available information repositories.

IN Training center "Interface" You will learn to use database management systems effectively: quickly find necessary information, navigate the database schema, create queries, develop and create databases.

Training will allow you not only to gain knowledge and skills, but also to confirm them by passing the appropriate exams for the status of a certified specialist. Experienced specialists in Microsoft DBMS SQL Server or Oracle may be interested in learning business intelligence systems. These tasks are quite complex, using cumbersome mathematical apparatus, but they allow not only to analyze ongoing processes, but also to make forecasts for the future, which is in demand by large companies. This is why business analytics specialists are in demand on the market, and the level of remuneration for their work is very, very decent, although qualified database specialists, administrators and developers also cannot complain about the low level of income. Come to our courses and get a sought-after and highly paid profession. We are waiting for you!

At the end of the course, final certification is carried out in the form of a test or by giving a grade by the teacher for the entire course of study based on the grades received by the student when checking the mastery of the material being studied based on grades for practical work performed during the training process.

Training center "Interface" provides consulting services on building business process models, design information systems, development of database structure, etc.

• Need help finding a course?
  Our goal is to provide training to professionals when and where they need it. It is possible to adjust course programs at the request of customers! We will tell you about what interests you, and not just about what is strictly fixed in the course program. If you need a course that you do not see on the schedule or on our website, or if you would like to take the course at a different time or location, please let us know at

It is simply and clearly explained what relational databases are in general, and what advantages Oracle DBMS have over their analogues. The demand for the systems of this corporation is constantly growing, more and more new versions are being released, each of which has its own characteristics. This guide provides a comprehensive description of the latest release, Oracle Database 11g. The first chapters are devoted to organizing the structure and architecture of 11g, its installation, launch and configuration. Then the security mechanisms are explained and the criteria for assessing compliance with the requirements are examined. Attention is paid to multi-user concurrency, data storage, distributed databases, OLTP systems, high availability, and hardware architectures. The latter include clusters, symmetric multiprocessors, Numa systems and gird computing.

All descriptions are illustrated with examples. Book “Oracle 11g. Fundamentals by Rick Greenwald, Robert Stakowiak and Jonathan Stern can be recommended to anyone who has not used Oracle before and is just planning to start working with these systems. At the same time, the manual is quite suitable as a reference for specialists already using these systems.

In the book “101 Oracle8i. Organization of network work” discusses the basic principles of building networks and the interaction of components network architecture Oracle, describes in detail the software and hardware that is needed to successfully connect computers and databases. The book offers step by step instructions on creating and configuring an Oracle network, with instructions provided with illustrations of screenshots. For your reference, general information about Internet protocols and encryption is provided.
This publication has been approved and recommended by Oracle itself.

Edition "Oracle. Programming on Java language» represents one of the most complete reference guides on creating software Java components for Oracle databases.
Having studied the proposed material, the reader will be able to independently build applications from individual components, while the applications will have the ability to access other objects in the Oracle environment. The book demonstrates how to work with the CORBA and Enterprise JavaBeans (EJB) server component models for distributed computing systems. Also covered in detail are issues related to the development process of EJB and CORBA components, development and implementation of component applications using SQLJ and Java and SQLJ. Provides step-by-step instructions for building JavaServer Page (JSP) applications. The reader will learn how to create database applications that manage object-relational and relational database schemas.
The book covers the following topics:
— ways of working in distributed computing environments;
— implementation of the construction of Enterprise JavaBeans and CORBA components;
— transaction management organizations;
— building a JSP page based on JavaBeans, CORBA, EJB components;
— creating database applications using servlets, JSP, XML pages;
— using the XML-SQL utility to perform queries and update operations.

Oracle9i Guide Programming in PL/SQL is designed for programmers who want to learn how to develop robust PL/SQL applications. The book discusses the main capabilities of databases different versions. The publication is intended to teach development, testing and debugging of PL/SQL applications in various development environments. The syntax of PL/SQL is considered, a description is given of variables, data types, operations, expressions, and control structures. The use of various PL/SQL development and execution environments and the use of Oracle9i multi-level constructs are shown.

The issues of ensuring data consistency using SQL transaction management instructions, creating and using functions, modules and procedures, using DML, triggers to solve complex data restrictions are considered. Explains the use of cursors to control the processing of SQL statements and for multi-row queries. The topic of using advanced PL/SQL tools, such as built-in dynamic SQL, external procedures And object types. The book is officially endorsed by Oracle Corporation.

The book “Oracle9iR2: Development and Operation of Database Warehouses” is devoted to the peculiarities of using data warehouses (WareHouse). The principles of building storages based on the Oracle9i DBMS are described. Theoretical and practical issues of designing data warehouses - one of the most complex branches of software engineering - are considered. It takes into account all existing design methodologies software, but their implementation is difficult due to the relative youth of this field and the lack of specialists working in it. The book can serve as a guide for various specialists in the field of Internet technologies, and will also be useful to analysts, marketers and other specialists who use data warehouses in their work.

"Oracle9i XML. Developing E-Commerce Applications Using XML Technology, written by Oracle XML Product Developers, focuses on developing and deploying transaction-based cross-platform Oracle applications using XML technology. This technology is now the industry standard for describing data when organizing Internet commerce and integrating applications e-business.

The book is aimed at teaching effective use Take advantage of the Oracle XML Developer Kit (XDK) to create, view, transform, and manage XML documents. The use of Oracle9i's built-in XML-enabled functions is clearly illustrated by various practical examples described in the book. Through this book, the reader will learn about the benefits of the Oracle XML framework and the Oracle XML Developer Kit and learn how to use them.

The book describes how to use parsers, generators, processes, viewers and various XDK utilities. The reader will learn how to develop Oracle9i applications using Java XML components, effective application new functions of XML SQL and PL/SQL, creation and use of applications for OAS and Oracle9iAS, focused on transaction processing. The book discusses how to manage various types of data - text, audio, graphics, video - using Oracle Text, describes the features of developing e-business applications running on the Web using the Oracle E-Business XML Services component, and much more.

The book by one of the leading specialists in his field, Jonathan Lewis, “Oracle. Fundamentals of Cost Optimization" is devoted to the most commonly used components of the Oracle data processing model, a description of the work of the optimizer with the statistics provided to it, and the reasons why its work may go wrong. Just a piece of code containing an Oracle data processing model, the cost optimizer applies that model to statistics on your data and attempts to efficiently convert the query you create into an executable plan. But since the model is often far from perfect, and the statistics are also not always ideal, the resulting execution plan may leave much to be desired. With information about why the optimizer might be going wrong, you can not only fix individual SQL statements, but also fine-tune the model, create more reliable statistics, and thereby completely improve problem areas.

The tutorial "Introduction to Oracle 10g" by J. Perry and J. Post provides an opportunity to familiarize yourself with basic principles operation of the Oracle database management system, practice applying basic skills and consolidate the acquired knowledge in memory. The proposed material is presented in detail and well illustrated with many examples. The book is written in simple and accessible language and will be a good purchase primarily for people who do not have much experience in dealing with databases. The tutorial comes with a dictionary of the most important and frequently used terms necessary for everyone who works with various systems database management. The book is intended for a wide range of readers, but can also be used as teaching aid for graduate students and students receiving education in the field of information technology.

PL/SQL is Oracle's very powerful procedural language, which has been the basis of applications built on Oracle technologies for the last fifteen years. PL/SQL was originally intended exclusively for developers. But today, it has become an important tool for database administration, as the direct responsibility of administrators for high database performance has increased, and the differences between developers and administrators are gradually erased. Oracle PL/SQL for Database Administrators is the very first book to cover PL/SQL from an administrative perspective. It should be noted that the presentation is focused on version 10g Release 2 of the program and begins with a brief overview of PL/SQL, which will be enough to familiarize the database administrator with the basics of this language and then begin working on it. The book then discusses security issues that can be related to database administration: row-level access control, encryption (both conventional methods and innovative methods are described). transparent encryption Oracle - TDE), random value generation and thorough auditing (FGA). Special attention The book focuses on ways to increase the performance of a database, as well as queries, through the use of table functions and cursors. It describes the use of the Oracle scheduler, which makes it possible to configure the systematic execution of tasks such as collecting statistics and monitoring a database.

The publication “Secrets of Oracle SQL”, using many examples, reveals to you how to use SQL tools in order to create not only convenient, but also extremely effective query support in the Oracle environment. This book will help you build efficient queries, which will work with collections and objects, use CASE and DECODE capabilities to create conditional logic when forming SQL queries and use to create window queries numerous analytical SQL functions. In addition, you will be able to master complex grouping functions, use ANSI-compliant join syntax, and learn to take full advantage of numerous SQL constructs, including the familiar groups, subqueries, joins, and much more. By studying the information on the pages of the book, you will not only become more confident in creating SQL queries, but also increase your education in this area, and, as a result, your productivity. Having learned to use new types for dates and times in your work and process hierarchical data, you will be able, using the properties of Oracle SQL, to solve very specific problems using previously unavailable techniques. The book “Oracle SQL Secrets” is intended for PL/SQL and Java programmers, database administrators.

First, a short lyrical digression. Company Oracle was created in 1977, in given time The director of the company is Larry Alison. The company has more than 36,000 employees (not including us users), in more than 90 countries. The company's annual turnover is more than $5.2 billion per year! This is how guys work! For example, compare with the Russian budget for last year! :) That's enough history for now.

Let's move on to the hardware requirements. Basically Oracle Personal Edition, installed on a Pentium 330 and 128 meg of RAM! Although it is possible to experiment with smaller volumes, I strongly advise against it, as you will end up with “brain trauma” trying, for example, to understand why everything works so slowly? For example, in my service I do not have machines lower than Celeron 1300 and 256 RAM. But it depends on your luck! So we will assume that NT4.0 or Advanced 2000 you are installed and in joyful anticipation of meeting with Oracle Server everything is already working.

Let me make a reservation right away: we will try everything on the platform NT. Why? Firstly, to clog your brains with an operating system like AIX, Solaris, Linux, I won’t, especially since when you grow wiser and you’ll figure it out on your own without me, it’s better to work with Oracle, What's on UNIX, What's on NT, from the client's point of view there is not much difference. I just want to try to show you the full power of this beast under the name without unnecessary friction ORACLE, and then the flag is in your hands, go ahead, study the operating systems and use it to the fullest!

Another sensitive point - MelkoMiagkie really don’t like everything that is produced in Larry Alison’s office, so I warn you right away not to experiment and try to cross on one server MS SQL And Oracle!!! :(The results will be the most deplorable!!! Better a separate machine and have fun for your own pleasure!!! And as for which server is better MS SQL or Oracle, I certainly won’t start a controversy!!! And I don’t recommend it to you either!!!

Let's proceed directly to the installation, since without this we can start working with Oracle, doesn’t make much sense, but knowing this process will be useful for you in the future! I'll lead everything from Oracle 8.1.5.0 and that's why! I have in my hands the most plausible and tested version of this server, I also have 8.1.7.0, but it has few differences from the first. I also have 9i, but I don’t have a travel server for it yet, so draw a conclusion. You can deviate from my instructions, fortunately I do not suffer from delusions of grandeur and, in general, everyone makes mistakes. All comments and additions will be accepted in order to increase the share of truth in this event of knowledge Oracle Server!

So, for those who do not have the distribution kit 8.1.5.0 and others like them, it is advisable to purchase it, or ask friends and acquaintances!!! Someone will definitely help and I sincerely believe in this, you still have time!!!

So, we install the disk in the compactor and listen carefully to the process AutoRun! Wow, what do we see!?

Oracle Universal Installer- this program will help us install and configure products Oracle on your server or workstation. I advise you to skip the offer to click on the “Installed products” button and not to “click” anywhere yet, but simply click the “next” button and enjoy the pleasant banner with the words “Welcome”!!!

Next we get to the “File Location” screen - here I think we need to go into a little more detail: position 1 is where your installation files are located, that is, the CD drive of your car, or something else. Position 2 is the system environment variable Oracle, which are used to search for server or client components and, accordingly, the path to these components. I don’t recommend changing anything here for the time being, but if your hands are very itchy, you can try, but I’m not responsible for the consequences!!! :)))))

So, it seems it has begun! Here it is, in fact, the server itself (it’s good that it’s not non-grato :). Now let's slow down a little and figure it out. Position 1 indicates that we select the server itself for installation, but this is not entirely true, because this same position will add NT and the client part to the server so that we can communicate with the server Oracle directly from the server! Wow, bullshit has begun! The second position is to install a clean client, it is also called “thick”! But more on that later. And finally, the third position, it’s not hard to guess for a programmer, so that he can give us something digestible for working with the server!

Assiduous people and those who are not yet tired of me, click the next button and see the next screen!

Ah!, here’s something interesting too! Now we are offered to choose the type of installation, for now choose “standard”, it is the simplest and asks the least questions, and most importantly, it does almost everything to the end itself and does not bother you with any stupid suggestions! Choose her and don’t be wise. Although, if someone chooses the minimum, that’s okay too, but you’ll decide the questions yourself along the way! But I don’t recommend touching the custom one at all, since you still don’t have enough knowledge. Click next and watch the next screen!

Here I advise you to leave the option as is CD-ROM, otherwise she will add another 133 meters to those seven hundred meters on your disk! So as always Next!!!

So - LET'S ARRIVE!!! I don't even know where to start! Let's start from the first position Global Database Name- because Oracle starting with the letter version -i, means that database domain names have the same rules as on the Internet, therefore get a fascist grenade! It is necessary to write Name->Dot->Domain, that is, for example, vasiapupkin.ru, or something else that comes to your consciousness inspired by the moment! I simply wrote proba.com, because “he forced himself to be respected and couldn’t have come up with anything better”! Second position SID that's all except .com, that is, the name of the database instance is global, another point will be associated with it, but more on that a little later! So, if you don’t follow the Name->Dot->Domain scheme here, you’ll have to do everything all over again!!! And your client will never find a copy of your database!

Now the summary has opened, just make sure that the installation language is Russian! And he’s Russian anyway, that’s nice!!! We’ll stop clicking further, since the long-awaited moment has arrived and with all our might we click “Install”!!!

The planet will begin to spin around the black hole, and the progress bar will begin its eternal blue movement to the right or blue, but what’s the difference!!! Let's watch and enjoy this wonderful spectacle!!!

The flight of the planet continues, but you and I are already thanked for choosing the server (shown by the arrow), hiding our pride, we continue to install the server!!!

So, here comes the crucial moment, everything seems to go by itself, but right now a database instance is born!!! A very responsible area, but for now “feed the dogs and don’t touch anything!!!” :))

Hooray!!! The database instance has been created, the instance has been launched and is ready to receive connections! But this is where the fun begins. This window tells about three tankers, no, not about those who drank three hundred!!! And those who are responsible for the Administration of the newly created database instance!!! DO NOT HURRY TO PRESS THE OK BUTTON!!! Take a print screen and copy it from the clipboard into paintbrush, that’s how I took these screenshots by the way!!! And that's why. These three have your keys to the database as an administrator. The first one's name is sys he is the eldest brother, his default password is change_on_install, the second name is system, default password manager! The middle one was this way and that, but the youngest was not a fool at all!!! His name is INTERNAL, his password (how to set it is a topic for a separate step) - correct ORACLE! Who they are and what they are eaten with, I’ll tell you later, while this is all on this moment, click OK!

Here's another way to check how the server is feeling. You need to open "Control Panel - Administration - Services" and find two services, one in the name ends with the same as SID base and the other ends TNSListener! So they should both be running and both should be standing Automatic!!! We won’t look into which of them and why for now.

Let's do this. Click on the first one (...PROBA) right click mouse and select the menu item Stop. Don't forget to launch Task Manager! If after the process stops the yellow memory consumption line drops sharply, it means the server has FALLED! No, or rather, the database instance is simply stopped, but there’s nothing wrong with that :)

Now right click there, only this time Start, HOORAY!!! Memory jumped up! The copy is back in service. The database is available and is waiting for connections again. Don’t disable the second service yet, and don’t touch the others either, we’ll deal with them later! This is where the conclusion comes from! The entire database instance lives in RAM!!! And this is one of the features of the server Oracle! And, it has a lot of features, which we will see later! That's all for now with the installation!