Search results “Hash tables in oracle”
What is a HashTable Data Structure - Introduction to Hash Tables , Part 0
This tutorial is an introduction to hash tables. A hash table is a data structure that is used to implement an associative array. This video explains some of the basic concepts regarding hash tables, and also discusses one method (chaining) that can be used to avoid collisions. Wan't to learn C++? I highly recommend this book http://amzn.to/1PftaSt Donate http://bit.ly/17vCDFx
Views: 761927 Paul Programming
ADS1: Hash tables for indexing
We discuss how a hash table can hold a k-mer index, as well as how to query it. Course page: https://www.coursera.org/course/ads1.
Views: 4822 Ben Langmead
Hash Partitioning in Oracle
The Video explains Hash partitioning in oracle and how it focuses on equal data distribution. It explains how hash partitioning uses partition joins to improve performance in VLDB by MPP.
Views: 5169 Tech Coach
Oracle Interview question : what is dual table in oracle
Oracle Interview question : what is dual table in oracle Oracle dual table is automatically created as part of installation in SYS schema. Dual table has one column called DUMMY of VARCHAR2(1) datatype. This table is useful for computing a constant expression with select statement List of all the SQL and PLSQL interview questions https://easy-learning-tech.blogspot.com/p/oracle-sql-plsql-interview-questions.html
Views: 398 Siva Academy
DBMS - Hash Index
DBMS - Hash Index Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Arnab Chakraborty, Tutorials Point India Private Limited
Oracle Tutorial || Oracle|Adv Sql | Partitioned Table Part - 1 by basha
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Tables and Tables Clusters in Oracle
https://dbagenesis.com/p/oracle-11g-advanced-dba DBA Genesis provides all you need to build and manage effective Oracle technology learning. We designed DBA Genesis as a simple to use yet powerful online Oracle learning system for students. Each of our courses is taught by an expert instructor, and every course is available on demand. Video talks about "what are table clusters inside Oracle database". One of video lessons from our Advanced DBA video course. Have a happy learning!
Views: 3870 DBA Genesis
Oracle Partitioning
Oracle Partitioning watch more videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Parth Panjab, Tutorials Point India Private Limited
Partitioning in Oracle Explained with Real project Examples : Introduction
This Video series will explain partitioning and its use cases referencing real project examples from different domain. It will explain what when and why of partitioning in a simple but elaborate manner. This is the 1st video which explains why partitioning is required and what are the advantages we gain from it. The following videos will explain when should we do it and how.
Views: 21767 Tech Coach
Indexing in Oracle :B-Tree,Bitmap Indexing
This Video is the 1st tutorial in the video series Indexing in Oracle , The video series explains in detail, What are indexes?It's types, what index should be used in which scenario and other important thing in basic terminology. Note :You may want to watch the video with a higher playback speed(1.25 if it suits you more)
Views: 13673 Tech Coach
06 How to configure Sub partition using Rang & Hash in oracle
You can create subpartitions in a composite partitioned table using a subpartition template. A subpartition template simplifies the specification of subpartitions by not requiring that a subpartition descriptor be specified for every partition in the table. Instead, you describe subpartitions only once in a template, then apply that subpartition template to every partition in the table. For interval-* composite partitioned tables, the subpartition template is the only way to define subpartitions for interval partitions. The subpartition template is used whenever a subpartition descriptor is not specified for a partition. If a subpartition descriptor is specified, then it is used instead of the subpartition template for that partition. If no subpartition template is specified, and no subpartition descriptor is supplied for a partition, then a single default subpartition is created. Specifying a Subpartition Template for a *-Hash Partitioned Table In the case of [range | interval | list]-hash partitioned tables, the subpartition template can describe the subpartitions in detail, or it can specify just the number of hash subpartitions. The following example creates a range-hash partitioned table using a subpartition template: CREATE TABLE emp_sub_template (deptno NUMBER, empname VARCHAR(32), grade NUMBER) PARTITION BY RANGE(deptno) SUBPARTITION BY HASH(empname) SUBPARTITION TEMPLATE (SUBPARTITION a TABLESPACE ts1, SUBPARTITION b TABLESPACE ts2, SUBPARTITION c TABLESPACE ts3, SUBPARTITION d TABLESPACE ts4 ) (PARTITION p1 VALUES LESS THAN (1000), PARTITION p2 VALUES LESS THAN (2000), PARTITION p3 VALUES LESS THAN (MAXVALUE) ); This example produces the following table description: Every partition has four subpartitions as described in the subpartition template. Each subpartition has a tablespace specified. It is required that if a tablespace is specified for one subpartition in a subpartition template, then one must be specified for all. The names of the subpartitions, unless you use interval-* subpartitioning, are generated by concatenating the partition name with the subpartition name in the form:
Views: 293 OnLinE ReSoUrCe
What is the HASH PARTITION in Oracle ?
Hi guys in my today scenario I'm going to explain with you What is the HASH PARTITION in Oracle, Oracle database Unbeatable,Unbreakable Platform.. #WhatisHASHPARTITION
Views: 7360 Oracle World
Hash Table Java Tutorial
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Views: 77 Genysis Lab
Local Vs Global Partitioned Index in Oracle 11g
The Video Explains the difference between Local Partitioned Indexes(Prefixed vs Non Prefixed Indexes). and Global Partitioned Index along with the challenges in maintaining Global partitioned Indexes when the underlying tables partitioned is dropped/truncated/Merged/Moved. Local Partitioned Index Shares the same boundaries as the table and are in the same number as table partitions they are widely used in DSS and DWH systems. While Global Partitioned Index are predominantly used in OLTP systems
Views: 5848 Tech Coach
What is the RANGE-HASH SUBPARTITIONS in Oracle ?
Hi guys in my today scenario I'm going to explain with you What is the RANGE-HASH SUB-PARTITIONS in Oracle,Oracle database #RANGE-HASHSUBPARTITIONS Unbeatable,Unbreakable Platform..
Views: 1409 Oracle World
What is a Hash Partition in Oracle
What is a Hash Partition in Oracle SQL Tutorial SQL Tutorial for beginners PLSQL Tutorial PLSQL Tutorial for beginners PL/SQL Tutorial PL SQL Tutorial PL SQL Tutorial for beginners PL/SQL Tutorial for beginners Oracle SQL Tutorial
Views: 839 TechLake
cluster, cluster types, Index and Hash Cluster - ETIT 427 - ADBA - IP University Syllabus
cluster, cluster types, Index and Hash Cluster - ETIT 427 - ADBA - IP University Syllabus For Students of B.Tech, B.E, MCA, BCA, B.Sc., M.Sc., Courses - As Per IP University Syllabus and Other Engineering Courses
KISS series on Partitioning: 04 How to create a hash partitioned table
Welcome to the KISS video series on Partitioning, where we take a more developer-centric look at how partitioning can make our applications more successful. In this session, we look at hash partitioning Scripts: https://livesql.oracle.com/apex/livesql/file/content_EVAZG9P72HTQ4Q695NT8MOTXG.html blog: https://connor-mcdonald.com ========================================­­============== Copyright © 2017 Oracle and/or its affiliates. Oracle is a registered trademark of Oracle and/or its affiliates. All rights reserved. Other names may be registered trademarks of their respective owners. Oracle disclaims any warranties or representations as to the accuracy or completeness of this recording, demonstration, and/or written materials (the “Materials”). The Materials are provided “as is” without any warranty of any kind, either express or implied, including without limitation warranties or merchantability, fitness for a particular purpose, and non-infringement.
Views: 640 Connor McDonald
Hash Partition in Oracle
This course has been designed to impart the in-depth knowledge about the partitioning types and architecture in the Oracle RDBMS. For more information on this course, please visit https://www.koenig-solutions.com/oracle-database-12-c-implement-partitioning-training.aspx
Views: 75 Koenig Solutions
Table Partitioning in Oracle Sql|Hash Partitioning|Range Partitioning|List Partitioning|Partitioning
Table Partitioning in Oracle Sql | Hash Partitioning | Range Partitioning | List Partitioning | Partitioning --------------------------------------------------------------------------------------------------------- hash partitioning,range partitioning,oracle hash partitioned index example,partition by range interval,when to use range partitioning,what is table partitioning,list partitioning,how to query partition table in oracle,partition, sql server, sql, partitioning in oracle, hash, performance, oracle, partitioning, list, range, interval partition, reference partition, composite partition, index partition, partition pruning, table partitioning, sql server table partition, table partition, hash partitioning, composite partitioning, sql server partitioning, sql server table partitioning, partition table, types of partitions, what is partition, advantages of partition, partition index, sql tutorials for beginners, sql expert, sql expert tutorials, database, oracle, table, online training,insert into oracle,oracle insert into multiple rows,create table oracle,oracle 12c alter table add identity column,oracle create table default value sysdate,collections in oracle pl sql with examples,Oracle 12c, database, oracle database (software), sql, sql developer, sql tutorials, how to create database using dbca, how to create database in oracle,oracle cloud, database 12c, dba genesis,database services, database, create, 11g, dba, db, beginner, Please Subscribe My Channel
Oracle 11g Hints Overview
In this Video tutorial we will discuss about Optimizer hints in Oracle. What is optimizer hint, when & why its needed. Different Category of hints. Description of mostly used hints. Demonstrate how query plan can change with the influence of hint.
Views: 51891 Anindya Das
How to insert Large Data sets in multiple tables part -1st
Hello friends in this video i explain how to insert multi-tables data at the same time from any table in different way in SQL. Oracle database Unbeatable,Unbreakable Platform..
Views: 1921 Oracle World
A Story of Indexes and Full Table Scans: Finding All the Red Sweets Part 1
"Why isn't Oracle using my index?!" is a common question people have when tuning SQL queries. In this episode Chris compares two methods for finding all the red candies from party bags he's prepared. He shows how these are like a full table scan and an index range scan. He goes on to compare the performance of these two approaches. He shows when a full table scan becomes more efficient than an index range scan and vice versa. ============================ The Magic of SQL with Chris Saxon Copyright © 2015 Oracle and/or its affiliates. Oracle is a registered trademark of Oracle and/or its affiliates. All rights reserved. Other names may be registered trademarks of their respective owners. Oracle disclaims any warranties or representations as to the accuracy or completeness of this recording, demonstration, and/or written materials (the “Materials”). The Materials are provided “as is” without any warranty of any kind, either express or implied, including without limitation warranties or merchantability, fitness for a particular purpose, and non-infringement.
Views: 7963 The Magic of SQL
AskTOM Office Hours: Hash Joins and Database In-Memory
Held on April 20 2018 Andy Rivenes (@TheInMemoryGuy) and Maria Colgan (@SQLMaria) focused on a deep dive into hash joins and how they are used with Database In-Memory to make joins lightning fast. The session began by reviewing how traditional hash joins work and then addressed Bloom filters and how Database In-Memory uses them to effectively turn hash joins into scan and filter operations. The use of Join Groups was then discussed as a way to further enhance join performance in 12.2 and beyond. AskTOM Office Hours offers free, monthly training and tips on how to make the most of Oracle Database, from Oracle product managers, developers and evangelists. https://asktom.oracle.com/ Oracle Developers portal: https://developer.oracle.com/ Sign up for an Oracle Cloud trial: https://cloud.oracle.com/en_US/tryit music: bensound.com
Views: 368 Oracle Developers
04 How to configure Hash partition in Oracle
Hash partitioning Use hash partitioning if your data does not easily lend itself to range partitioning, but you would like to partition for performance and manageability reasons. Hash partitioning provides a method of evenly distributing data across a specified number of partitions. Rows are mapped into partitions based on a hash value of the partitioning key The following example shows how to create a hash partition table. The following example creates a hash-partitioned table. The partitioning column is partno, four partitions are created and assigned system generated names, and they are placed in four named tablespaces (tab1,tab2, ...). CREATE TABLE products (partno NUMBER, description VARCHAR2 (60)) PARTITION BY HASH (partno) PARTITIONS 4 STORE IN (tab1, tab2, tab3, tab4);
Views: 764 OnLinE ReSoUrCe
DBMS Indexing: The Basic Concept
A quick introduction to the concept of indexing in RDBMSs
Views: 161036 Brian Finnegan
21. Cryptography: Hash Functions
MIT 6.046J Design and Analysis of Algorithms, Spring 2015 View the complete course: http://ocw.mit.edu/6-046JS15 Instructor: Srinivas Devadas In this lecture, Professor Devadas covers the basics of cryptography, including desirable properties of cryptographic functions, and their applications to security. License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Views: 69090 MIT OpenCourseWare
Oracle Hints Tutorial for improving performance
Oracle Hints Tutorial for improving performance APPEND PARALLEL JOIN INDEX NO_INDEX SELECT /*+ FIRST_ROWS(10) */ * FROM emp WHERE deptno = 10; SELECT /*+ ALL_ROWS */ * FROM emp WHERE deptno = 10; SELECT /*+ NO_INDEX(emp emp_dept_idx) */ * FROM emp, dept WHERE emp.deptno = dept.deptno; SELECT /*+ INDEX(e,emp_dept_idx) */ * FROM emp e WHERE e.deptno = 10; -- SELECT /*+ INDEX(scott.emp,emp_dept_idx) */ * FROM scott.emp; SELECT /*+ AND_EQUAL(e,emp_dept_idx) */ * FROM emp e; SELECT /*+ INDEX_JOIN(e,emp_dept_idx) */ * FROM emp e; SELECT /*+ PARALLEL_INDEX(e,emp_dept_idx , 8) */ * FROM emp e; SELECT /*+ LEADING (dept) */ * FROM emp, dept WHERE emp.deptno = dept.deptno; SELECT /*+ PARALLEL(8) CACHE (e) FULL (e) */ * FROM emp e ; SELECT /*+ PARALLEL FULL (e) */ * FROM emp e ; SELECT /*+ PARALLEL USE_MERGE (emp dept) */ * FROM emp, dept WHERE emp.deptno = dept.deptno; -- SORT Merge Join SELECT /*+ PARALLEL USE_HASH (emp dept) */ * FROM emp, dept WHERE emp.deptno = dept.deptno; -- Hash Join SELECT /*+ PARALLEL */ * FROM emp e ; INSERT /*+ APPEND */ INTO mytmp select /*+ CACHE (e) */ *from emp e; commit;
Views: 6468 TechLake
B-Tree Indexes
In this video, I'd like to take a look at B-tree indexes and show how knowing them can help design better database tables and queries.
Advanced Topics in Programming Languages: A Lock-Free Hash Table
Google Tech Talks March 28, 2007 ABSTRACT I present a lock-free concurrent Hash Table implementation with better single-thread performance than most Hash Tables, and better multi-thread performance than all other implementations I tried. I demonstrate scaling up to 768 CPUs even with high mutation rates. I show correctness by looking at the problem in a very different light than the usual "happens-before" / memory-order / fencing style of thinking. Speaker: Dr. Cliff Click Dr. Cliff Click, Azul Systems. Chief JVM Architect, Distinguished Engineer With more than twenty-five years experience developing compilers Cliff serves as Azul Systems' Chief JVM Architect. Cliff joined Azul in 2002 from Sun Microsystems where he was the architect and lead developer of the HotSpot Server Compiler, a technology that has delivered dramatic improvements in Java performance since its inception. Previously he was with Motorola where he helped deliver industry leading SpecInt2000 scores on PowerPC chips, and before that he researched compiler technology at HP Labs. Cliff has been writing optimizing compilers and JITs for over 15 years. He is invited to speak regularly at industry and academic conferences, and has published many papers about HotSpot technology. Cliff holds a PhD in Computer Science from Rice University. Google engEDU Speaker: Cliff Click
Views: 21156 GoogleTalksArchive
Hash Values
This video is about Hash Values
Views: 2793 Nick Marriott
Ways of generating EXECUTION PLAN in Oracle Database
Learn how to generate execution plan in oracle database in many ways
Views: 3426 OrSkl Academy
What's Email Hashing?
There is a lot of talk about “identity” in the advertising and marketing space right now with companies like Salesforce and Oracle making it easier than ever for brands to take their customer identity data (specifically email addresses) and use it to reach these customers in paid media channels likes of Google, Facebook, LiveIntent and Twitter – a process known as CRM Retargeting. But while this process has gotten easier, many brands are still asking the same question Gandalf asks Frodo about the ring: Is it secret? Is it safe? That’s why this week, we’re taking a moment to explain what “hashing” means, and how it de-identifies the email address into a secure and unique method for leveraging a brand’s CRM data. Love the awesome content you're seeing? Check out our other videos and be sure to subscribe: https://blog.liveintent.com/category/liveintentional/
Views: 1191 LiveIntent Video
How to reduce Buffer Busy Waits using Hash Partitioned Indexes
The clip explains how Buffer Busy Waits are being caused and how they can be reduced with Hash Partitioned Indexes. A text version is here: https://uhesse.com/2016/12/02/how-to-reduce-buffer-busy-waits-with-hash-partitioned-indexes-in-oracle/
Oracle views explained with real project examples
This video demonstrates what are oracle views and why and when you should use them. It explains abstraction and security that the views offer with different real project examples. The DML operations you can perform on views and the restrictions. Syntax : CREATE VIEW view_name AS SELECT columns FROM tables [WHERE conditions]; Please do watch the video and leave your inputs/questions in the comments section, If you like the video give a thumbs up and share it with your friends who can benefit from this.
Views: 5102 Tech Coach
Hashing: Why & How?
Why do we wish to reduce a long list to a short one? How to do it, so that the short list will identify the long list. How to do it so that it is impossible to identify the long list from the short one, and the implications of the fact that many long lists share the very same short list. Hashing configurations: straight encryption, MD4, MD5, SHA-1, SHA-2.
Views: 142708 Gideon Samid
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Index Organized Tables and Examples
Index Organized Tables and Examples watch more videos at https://www.tutorialspoint.com/videotutorials/index.htm Lecture By: Mr. Parth Panjab, Tutorials Point India Private Limited
SQL Advanced Videos #5: Hash Join
The last of the three physical join operator and by far the most interesting one. However we pay a price in terms of memory for that interesting join :) #sql #database #hashjoin #hash #join
Views: 1836 SQL TV
In this video, I will describe the 3 Join Operators SQL Server uses and the reason why it comes to the individual selections by the Optimizer. Please check my blog azizsharif.blogspot.com for more videos!
SQL Server Quickie #13 - Hash Join Operator
In this SQL Server Quickie I'm talking about the Hash Join operator in SQL Server. You can find the scripts that were used for the demonstration here: http://www.sqlpassion.at/archive/2014/04/29/sql-server-quickie-13-hash-join-operator/
Views: 12281 SQLpassion
Focus on Hash Joins - Using Database In-Memory
Ask TOM Office Hours demo - Focus On Hash Joins This demonstration reviews how Database In-Memory uses Hash Joins and Bloom filters to provide up to a 10x performance improvement. You can see the full session and join us for more Office Hours sessions at https://asktom.oracle.com/pls/apex
PL/SQL: Brief on Associative Arrays
In this tutorial, you'll learn the points to be noted on AA PL/SQL (Procedural Language/Structured Query Language) is Oracle Corporation's procedural extension for SQL and the Oracle relational database. PL/SQL is available in Oracle Database (since version 7), TimesTen in-memory database (since version 11.2.1), and IBM DB2 (since version 9.7).[1] Oracle Corporation usually extends PL/SQL functionality with each successive release of the Oracle Database. PL/SQL includes procedural language elements such as conditions and loops. It allows declaration of constants and variables, procedures and functions, types and variables of those types, and triggers. It can handle exceptions (runtime errors). Arrays are supported involving the use of PL/SQL collections. Implementations from version 8 of Oracle Database onwards have included features associated with object-orientation. One can create PL/SQL units such as procedures, functions, packages, types, and triggers, which are stored in the database for reuse by applications that use any of the Oracle Database programmatic interfaces. PL/SQL works analogously to the embedded procedural languages associated with other relational databases. For example, Sybase ASE and Microsoft SQL Server have Transact-SQL, PostgreSQL has PL/pgSQL (which emulates PL/SQL to an extent), and IBM DB2 includes SQL Procedural Language,[2] which conforms to the ISO SQL’s SQL/PSM standard. The designers of PL/SQL modeled its syntax on that of Ada. Both Ada and PL/SQL have Pascal as a common ancestor, and so PL/SQL also resembles Pascal in several aspects. However, the structure of a PL/SQL package does not resemble the basic Object Pascal program structure as implemented by a Borland Delphi or Free Pascal unit. Programmers can define public and private global data-types, constants and static variables in a PL/SQL package.[3] PL/SQL also allows for the definition of classes and instantiating these as objects in PL/SQL code. This resembles usage in object-oriented programming languages like Object Pascal, C++ and Java. PL/SQL refers to a class as an "Abstract Data Type" (ADT) or "User Defined Type" (UDT), and defines it as an Oracle SQL data-type as opposed to a PL/SQL user-defined type, allowing its use in both the Oracle SQL Engine and the Oracle PL/SQL engine. The constructor and methods of an Abstract Data Type are written in PL/SQL. The resulting Abstract Data Type can operate as an object class in PL/SQL. Such objects can also persist as column values in Oracle database tables. PL/SQL is fundamentally distinct from Transact-SQL, despite superficial similarities. Porting code from one to the other usually involves non-trivial work, not only due to the differences in the feature sets of the two languages,[4] but also due to the very significant differences in the way Oracle and SQL Server deal with concurrency and locking. There are software tools available that claim to facilitate porting including Oracle Translation Scratch Editor,[5] CEITON MSSQL/Oracle Compiler [6] and SwisSQL.[7] The StepSqlite product is a PL/SQL compiler for the popular small database SQLite. PL/SQL Program Unit A PL/SQL program unit is one of the following: PL/SQL anonymous block, procedure, function, package specification, package body, trigger, type specification, type body, library. Program units are the PL/SQL source code that is compiled, developed and ultimately executed on the database. The basic unit of a PL/SQL source program is the block, which groups together related declarations and statements. A PL/SQL block is defined by the keywords DECLARE, BEGIN, EXCEPTION, and END. These keywords divide the block into a declarative part, an executable part, and an exception-handling part. The declaration section is optional and may be used to define and initialize constants and variables. If a variable is not initialized then it defaults to NULL value. The optional exception-handling part is used to handle run time errors. Only the executable part is required. A block can have a label. Package Packages are groups of conceptually linked functions, procedures, variables, PL/SQL table and record TYPE statements, constants, cursors etc. The use of packages promotes re-use of code. Packages are composed of the package specification and an optional package body. The specification is the interface to the application; it declares the types, variables, constants, exceptions, cursors, and subprograms available. The body fully defines cursors and subprograms, and so implements the specification. Two advantages of packages are: Modular approach, encapsulation/hiding of business logic, security, performance improvement, re-usability. They support object-oriented programming features like function overloading and encapsulation. Using package variables one can declare session level (scoped) variables, since variables declared in the package specification have a session scope.
Views: 6459 radhikaravikumar