Home
Search results “Duplicate rows oracle delete”
How to Delete the Duplicate Records in oracle
 
03:44
http://oracletemple.blogspot.in/ How to Delete the duplicate records How delete the duplicate rows ? Tips: - Always take extra caution while deleting records. 1. First identify the duplicates using select. 2. Double verify those are actual ‘duplicates’ or not 3. Take backup if necessary 4. Apply commit only if you are sure. -~-~~-~~~-~~-~- Please watch: "difference between delete and truncate" https://www.youtube.com/watch?v=7b6wQ3Qumgg -~-~~-~~~-~~-~- ------------------------------------------------------------------ Below is link for Useful Pl/SQL Books http://goo.gl/XMy0tt ---------------------------------------------------------- Watch More... What is Parameterized Cursor in Oracle https://www.youtube.com/watch?v=JMKwHlVi6-A What is autonomous transaction in Oracle. https://www.youtube.com/watch?v=gyvFajpfoWE What are Constraints available in Oracle. https://www.youtube.com/watch?v=WivhdLXQklQ What is Mutation Error and How to avoid mutation. https://www.youtube.com/watch?v=CbWNCyW18Bs 5 Effective way to delete Duplicate rows https://www.youtube.com/watch?v=1wtTtnc87Oc What is Difference between Delete and Truncate https://www.youtube.com/watch?v=7b6wQ3Qumgg
Views: 24703 Ram Gupta
Oracle SQL Interview Questions : Delete duplicate records
 
04:48
This is the 1st video of the video series Oracle Interview questions. The video Demonstrates how to delete duplicate records in Oracle. I will cover all the major common questions asked in SQL and PL/SQL interviews as a part of this series. Please do contribute questions that you have come across in any of your interviews
Views: 4209 Tech Coach
HOW TO IDENTIFY AND DELETE DUPLICATE ROWS USING ROWID AND GROUPBY IN ORACLE SQL
 
07:53
This video demonstrates examples on how to find and delete duplicate records from a table. The video gives simple and easy to understand examples on finding duplicate records from a table using group by and having clause and row_number function. It also shows the ways in which duplicates can be deleted very efficiently using the rowid of that record. You can get the code from our website http://oracleplsqlblog.com/FullBlog/FullBlog/21
Views: 12537 Kishan Mashru
SQL Tutorial : How To Delete Duplicate Records in SQL Oracle
 
07:43
SQL Tutorial : How To Delete Duplicate Records in SQL 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: 5042 TechLake
Part 4   Delete duplicate rows in sql
 
03:26
Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2014/05/part-4-delete-duplicate-rows-in-sql.html In this video, we will discuss deleting all duplicate rows except one from a sql server table. SQL Script to create Employees table Create table Employees ( ID int, FirstName nvarchar(50), LastName nvarchar(50), Gender nvarchar(50), Salary int ) GO Insert into Employees values (1, 'Mark', 'Hastings', 'Male', 60000) Insert into Employees values (1, 'Mark', 'Hastings', 'Male', 60000) Insert into Employees values (1, 'Mark', 'Hastings', 'Male', 60000) Insert into Employees values (2, 'Mary', 'Lambeth', 'Female', 30000) Insert into Employees values (2, 'Mary', 'Lambeth', 'Female', 30000) Insert into Employees values (3, 'Ben', 'Hoskins', 'Male', 70000) Insert into Employees values (3, 'Ben', 'Hoskins', 'Male', 70000) Insert into Employees values (3, 'Ben', 'Hoskins', 'Male', 70000) The delete query should delete all duplicate rows except one. Here is the SQL query that does the job. PARTITION BY divides the query result set into partitions. WITH EmployeesCTE AS ( SELECT *, ROW_NUMBER()OVER(PARTITION BY ID ORDER BY ID) AS RowNumber FROM Employees ) DELETE FROM EmployeesCTE WHERE RowNumber ] 1
Views: 375231 kudvenkat
How to delete duplicate records from a table in oracle
 
02:01
Let c how to remove duplicates from a table..I have one table here 'student' It has two duplicate records. 3 joe 4 robert These two records has duplicates. So I have to remove them. I can remove them using rowid functionality using one subquery. You can give different column names in GROUP BY clause. to identify the duplicate record. You can give just primary key values also. Duplicate rows are deleted now... Query used in video: delete from student where rowid not in (select min(rowid) from student group by sno,sname); Thanks for watching...:)
Views: 15896 WingsOfTechnology
How to Delete Duplicate records(rows) in SQL Server
 
10:21
This video shows to find duplicate records and how to delete Duplicate records in a table.This video explains , best 5 methods to delete duplicate records in table.In this way we can maintain Accuracy and consistence of data data in Database .
Views: 42751 Tech Jago
How to delete duplicate rows(records) in oracle using rowid
 
02:53
In this video I've explained how do you delete duplicate rows in oracle using a psuedocolumn oracle rowID.
Views: 14 Pro Mentor
How to delete duplicate rows in SQL
 
02:57
How to delete duplicate rows in SQL
Views: 2605 X Admin
Delete Duplicate Records in Oracle Database
 
08:45
delete duplicate records in oracle using analytical function, delete duplicate records in oracle without using subquery, delete duplicate records in oracle without using rowid, find duplicate rows in oracle, oracle remove duplicates from query results, oracle delete duplicate rows but keep original, how to find duplicate records in oracle using rowid
Views: 97 Adam Tech
how to delete duplicate row in oracle or pl/sql
 
02:40
simple create new table and store distinct data of old table in new table. after drop old table and rename new table to old table name..........
Views: 27 EasyWay Coding
Delete Duplicate rows in sql (Simple Way)
 
01:32
Delete Duplicate rows in sql rows
Views: 2663 AngularTech
Identify and Delete Duplicate records (rows) - SQL Server
 
10:08
Identify and Delete Duplicate records/rows. Check and get the script here in my blog: http://sqlwithmanoj.com/2011/10/14/identify-delete-duplicate-records-from-a-table/ For more updates like my page in FB: https://www.facebook.com/sqlwithmanoj
Views: 25242 SQL with Manoj
ORACLE SQL AND PL/SQL INTERVIEW QUESTION : DELETE DUPLICATE RECORDS FROM  A TABLE(3 ways)
 
13:15
This video tutorial demonstrates about how we can delete duplicate records from a table, the video shows 3 different ways to delete duplicate record from a table, one using Group by, second one by using correlated joins and third on by using rownum analytical function You can get the code from our website http://oracleplsqlblog.com/FullBlog/FullBlog/21
Views: 6100 Kishan Mashru
How to delete duplicate rows in sql | Identify duplicate rows in sql server
 
06:02
This video talks about How to delete duplicate rows in sql Identify duplicate rows in sql server duplicate rows in sql delete rows in sql server delete duplicate records in sql server Part of SQL Server interview questions and answers sq server tutorials
Views: 1414 Training2SQL MSBI
delete duplicate rows in sql
 
05:08
how to delete duplicate record in sql databse.
Views: 396 Sql Server
Delete duplicate records from a table in Oracle SQL.
 
07:27
How to search or delete duplicate records using SQL or PL SQL. Using select or delete clause to search or delete duplicate rows from tables in PL SQL.
Views: 1946 Subhroneel Ganguly
Delete Duplicates in SQL - SQL Training Online
 
05:36
http://www.sqltrainingonline.com Delete Duplicates in SQL Server - SQL Training Online In this video, I show you two different techniques to remove duplicate records in a SQL Server 2012 table. I don't use the SQL distinct operators, but I actually group the data and apply unique row identifiers to make the SQL delete easier. Both of the SQL delete statements involve SQL Server CTE statements and use the Row_Number operator to assist in the process. With the operator, you can identify the duplicate rows You can get the sample script to run the test yourself at http://www.sqltrainingonline.com/how-to-remove-duplicate-rows-in-sql-server/. Let me know what you think by commenting or sharing on twitter, facebook, google+, etc. If you enjoy the video, please give it a like, comment, or subscribe to my channel. You can visit me at any of the following: SQL Training Online: http://www.sqltrainingonline.com Twitter: http://www.twitter.com/sql_by_joey Google+: https://plus.google.com/#100925239624117719658/posts LinkedIn: http://www.linkedin.com/in/joeyblue Facebook: http://www.facebook.com/sqltrainingonline
Views: 30184 Joey Blue
how to delete duplicate rows in  Sql server?
 
07:10
It is the very common interview question .Please watch full video for more detail.Please find script below, How to duplicate Rows in table ?
Views: 2584 SqlIsEasy
How to Delete Duplicate Record from Table
 
07:08
Hi friends today i will show you a basic sql query to delete th duplicate entry from table usinf rownum & rowid. #DeleteDuplicateRecord Oracle database Unbeatable,Unbreakable Platform..
Views: 2777 Oracle World
SQL Interview Question - How to Delete Duplicate Rows in a table
 
04:26
Watch this video to understand how can we delete duplicate records from a table. This is one of the most frequently asked interview questions.
Views: 19009 Disha Saxena
How To Delete Duplicate Rows In Sql Server
 
03:27
How to delete duplicate rows in sql server. This video shows how you can delete duplicate rows in sql server without deleting the original record using CTE(Common Table Expression). Script download link :: https://goo.gl/8szALM Text Article on this topic : ➤ https://goo.gl/XVXUuX Best SQL Server Books from Amazon (Affiliate) : ➤ http://geni.us/Y7dWvnO Buy me a Coffee (Channel Support By Donation) ➤ https://goo.gl/bPcyXW Subscribe to this channel ➤ https://goo.gl/RFY5C2 Link to this video ➤ https://youtu.be/fwz0om3IUts Our Website ➤ http://www.codaffection.com ______________ ⌘ Social Media Links ________________ Blog : http://www.codaffection.com Facebook : https://www.facebook.com/codaffection Google plus : https://plus.google.com/+codaffection Twitter : https://twitter.com/codaffection Youtube : https://youtube.com/codaffection ______________ ↪ About this Channel ________________ CodAffection - for passionate programmers. This channel is all about teaching and inspiring developers to build applications/ websites in various technologies like Angular, NodeJS, Asp.Net MVC, JavaScript, SQL, React, Python etc. 2 Videos per Week - 12:30 PM UTC On MON and THU ______________ ₪ All Playlist ________________ https://goo.gl/gvjUJ7 : Asp.Net MVC https://goo.gl/ahk39S : Angular 5 https://goo.gl/viJcFs : Node JS https://goo.gl/itVayJ : Web API https://goo.gl/YJPPAH : MEAN Stack https://goo.gl/s1zJxo : C# Tutorial https://goo.gl/GXC2aJ : Asp.Net WebForm https://goo.gl/vHS9Hd : C# WinForm https://goo.gl/MLYS9e : MS SQL https://goo.gl/Ha71kq : Angular 4 https://goo.gl/5Vou7t : Crystal Report https://goo.gl/EPZ69B : Common C# Excercises https://goo.gl/qEWJCs : CG Exercises in C Program
Views: 7085 CodAffection
SQL: Delete Vs Truncate Vs Drop
 
08:27
In this tutorial, you'll learn the difference between delete/drop and truncate. 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: 74847 radhikaravikumar
Delete duplicate rows in SQL Server Tamil
 
04:17
Click here to Subscribe to IT PORT Channel : https://www.youtube.com/channel/UCMjmoppveJ3mwspLKXYbVlg A common table expression (CTE) can be thought of as a temporary result set that is defined within the execution scope of a single SELECT, INSERT, UPDATE, DELETE, or CREATE VIEW statement. A CTE is similar to a derived table in that it is not stored as an object and lasts only for the duration of the query. Unlike a derived table, a CTE can be self-referencing and can be referenced multiple times in the same query
Views: 352 IT Port
SQL and PLSQL INTERVIEW 1-Find and Delete Duplicate Rows
 
02:19
How to find and delete Duplicate Rows
Views: 209 Manikandan R
Oracle  ||  SQL Duplicate Rows by Srikanth
 
10:57
DURGASOFT is INDIA's No.1 Software Training Center offers online training on various technologies like JAVA, .NET , ANDROID,HADOOP,TESTING TOOLS , ADF, INFORMATICA,TABLEAU,IPHONE,OBIEE,ANJULAR JS, SAP... courses from Hyderabad & Bangalore -India with Real Time Experts. Mail us your requirements to [email protected] so that our Supporting Team will arrange Demo Sessions. Ph:Call +91-8885252627,+91-7207212428,+91-7207212427,+91-8096969696. http://durgasoft.com http://durgasoftonlinetraining.com https://www.facebook.com/durgasoftware http://durgajobs.com https://www.facebook.com/durgajobsinfo............
MySQL - Remove Duplicate Rows
 
05:23
Thank you for Watching! Please do subscribe. Step 1 CREATE TABLE duplicate_table LIKE orignal_table; Step 2 INSERT INTO duplicate_table SELECT * FROM orignal_table GROUP BY column; Step 3 DROP TABLE orignal_table; ALTER TABLE duplicate_table RENAME TO orignal_table;
Views: 623 ZUUPEE TECH
HOW TO DELETE DUPLICATE RECORDS IN SQL PART1
 
05:59
Compleatly DELETE DUPLICATE RECORDS IN SQL PART1
Views: 1341 Tech mohan
Find Duplicate Rows in SQL - Select Statement Tutorial
 
02:06
Find duplicate row values in a field or multiple fields in SQL Server table with this tutorial. Do this for one column, or multiple columns. Uses SQL Server Management Studio for the demonstration.
Views: 49682 Edward Kench
Learn Oracle SQL : Filtering Duplicate Rows ( The DISTINCT Clause )
 
04:15
http://bit.ly/oracle-sql-course | Get the complete course today. Learn Oracle SQL : Filtering Duplicate Rows ( The DISTINCT Clause ): In this video, I show you how you can use the DISTINCT clause to remove duplicate rows from the results of your queries. This is an excerpt of the course " Oracle SQL From Scratch " which you can get at a discounted price here: http://bit.ly/oracle-sql-course You can find additional Oracle SQL related articles and educational content in my blog here: http://standout-dev.com/
Views: 268 Oracle SQL
Ways to delete duplicate records: Oracle
 
26:26
Topic : Ways to delete duplicate records: Oracle 20th Video of this Series Comments/Suggestions are welcome get in touch with us, by mailing [email protected] for Upcoming trainings. This is an Unedited Video from the Live sessions on Sql (RDBMS) I will be posting a complete series of these tutorials on this channel, If you would like to be notified every time i post something ; Please subscribe to this channel and press the bell icon. Other Videos of same series : https://www.youtube.com/watch?v=b19w2vs8IE0 https://youtu.be/b19w2vs8IE0 https://youtu.be/Mtp81d-YBpI More Theory: https://www.wikihow.com/Delete-Duplicate-Records-in-Oracle
Views: 38 CodeSmith 001
How to delete duplicate records from SQL Server
 
06:58
This video is a step by step process of writing a query to remove duplicates in a SQL Server table.
Views: 794 Alireza Aliabadi
P#8 How to Delete duplicate records in oracle SQL Database - interview question by Rakesh Malviya
 
01:51
Oracle SQL Course /Online Training Tutorial on Delete duplicate records from the Oracle Database Oracle SQL Complete Tutorial/Training/Course for the beginner: https://www.youtube.com/watch?v=3v4s3XMw4q0&list=PLiLpmqwkwkCt0QeXD8j7BwIoOaBGBRrZC You will get Following question answer: 1.how to delete duplicate records in SQL 2.how to delete duplicate rows in Oracle 3.remove duplicate rows in SQL query result 4.how to eliminate duplicate rows in SQL without using distinct 5.delete duplicate rows in SQL 6.delete duplicate rows in SQL using rowid 7.find duplicate rows in Oracle 8.Query to delete duplicate records 9.oracle delete duplicate rows but keep original 10.delete duplicate rows and need to keep one from all of them in mysql 11.removing duplicates except one 12.Ways to delete duplicate records Oracle follow me on: Facebook Page: https://www.facebook.com/LrnWthr-319371861902642/?ref=bookmarks Contacts Email: [email protected] Instagram: https://www.instagram.com/equalconnect/ Twitter: https://twitter.com/LrnWthR #equalConnectCoach #rakeshmalviya #OracleTutorial
Views: 69 EqualConnect Coach
SQL CTE Examples | SQL Delete Duplicate Rows | Identify duplicate rows in sql server
 
10:48
Video talks about how to write SQL CTE with examples Common table expressions in SQL server CTE examples in SQL server How to delete duplicate rows in sql server identify duplicate rows in sql server delete duplicate rows in sql server Row Number in SQL server Common table expression with examples Partition in SQL server Order By in SQL server Step by step SQL Training videos SQL Tutorial For more technology videos .. please subscribe to my channel.. https://www.youtube.com/channel/UCgWvQ6cBxZwABl_hL48ayXg
Views: 1754 Training2SQL MSBI
Deleting Duplicate Rows Using the Row_Number() Windows Function
 
08:47
In SQL Server how to delete duplicate rows in a table that does not have a unique column values.
Views: 151 Coopman Greg
How to find duplicate records in table sql
 
06:32
There are various times when we need to find duplicate records in SQL Server. It is possible to find duplicates using DISTINCT, ROW NUMBER as well as the GROUP BY approach. ------------- May be you like this -------------- umbraco playlist : https://www.youtube.com/watch?v=zoefdruzmGE&list=PLv0T7WlllnSnYRedhwL8x-atkVxrSdd3m Angularjs playlist : https://www.youtube.com/watch?v=KXjD1RiAz1U&list=PLv0T7WlllnSkCfNftTNY8tWqCFWT0sIMd jquery playlist : https://www.youtube.com/watch?v=jVncasz_iyw&list=PLv0T7WlllnSkkNahiiWu_GMXq49X5ccfe F Wcf playlist : https://www.youtube.com/watch?v=NB4k0RC6vl0&list=PLv0T7WlllnSmcGHacEQnLgKvitcJEsSl6 c# playlist: https://www.youtube.com/watch?v=ZrP0NKbsr8s&list=PLv0T7WlllnSl9pZWMaMGsyoAmqZtW4gM0 Duplicate records can create problems sometimes when displaying reports or performing a Multiple Insert update. Finding duplicate records in a database needs further investigation. In some cases, duplicate records are positive, but it all depends on the data and the database design as well. For example, if a customer has ordered the same product twice on the same date with the the same shipping and billing address, then this may result in a duplicate record.
Views: 17276 Go Freelancer
How will you eliminate duplicate values from a query result in MySQL?
 
02:45
Q. How will you eliminate duplicate values from a query result in MySQL? MySQL provides DISTINCT keyword to remove duplicates from a query result. With DISTINCT keyword, a value will be displayed only once. Eg. SELECT DISTINCT NAME FROM EMPLOYEE; This query will return each name in Employee table only once. Q. How will you get the size of data in a MySQL table? In MySQL, there is an information_schema that contains the TABLES object. We can run a query on TABLES to get the size of data in a table. Eg. If we have a table named EMPLOYEE, the query to get the size of data will be as follows: SELECT table_name "Table Name",sum( data_length + index_length ) / 1024 / 1024 "Table Size (MB)" FROM information_schema.TABLES WHERE table_name='EMPLOYEE'; Learn more MySQL interview questions, join our popular MySQL Interview Questions Preparation Course with more than 50 questions for $10 only today!! https://www.udemy.com/mysql-interview-questions-preparation-course/?couponCode=KPOWER10 Source: http://www.knowledgepowerhouse.com/video-course
Views: 1781 Knowledge Powerhouse
MySQL Tutorial 1 - Remove Duplicate Rows from MySQL Table
 
03:20
How to remove duplicate rows from a MySQL database table. The process should be similar for other kinds of databases I imagine. Have a wonderful day and happy coding!
Views: 21416 Anthony Vipond
Delete duplicate rows in sql | wafa ki dunia
 
01:31
Part 4 Delete duplicate rows in sql | wafa ki dunia delete duplicate records in sql server, delete duplicate records in sql server using row_number, delete duplicate records in sql server using rowid, delete duplicate records in sql server 2008, delete duplicate records in sql w3schools, how to remove duplicates in sql query, how to delete duplicate rows in oracle, delete duplicate rows in mysql, Page navigation,
Views: 6 wafa ki dunia
Oracle SQL Tutorial 19 - ON DELETE (SET NULL and CASCADE)
 
05:59
Welcome everyone! Something you need to consider when you are creating foreign keys is what happens if you delete the parent? As a reminder, the parent is the row that has the value you are referencing in the row that has a foreign key. Why is this something important to consider? It's important because foreign keys need to protect us from two primary things, unacceptable INSERT statements, and unacceptable DELETE statements. Let's see what happens when we try to insert incorrect data into the table with the foreign key: INSERT INTO projects VALUES (1, 'Update website homepage', 'CalebCurry') The response tells us plainly that there is no such user in the users table. So this works correctly. Deleting data on the other hand works a bit differently because the database does not know what you want to do with the child row when you delete the parent from the parent table. By default, we will get an error message that prevents the parent from being deleted, but there are some other options. How do we configure this? This is where the ON DELETE statement comes in. We add the keywords ON DELETE right after the foreign key and then we can give it the option of CASCADE or SET NULL. CASCADE means that if we delete the parent, we are also going to delete the child. In our situation what that means is that if somebody creates a project in our project table and then that persons account gets deleted, all of the projects he owns will also be deleted. CASCADE: CREATE TABLE projects( project_id NUMBER, Project_name VARCHAR2(50 CHAR) UNIQUE, creator VARCHAR2(50 CHAR) NOT NULL, CONSTRAINT projects_pk PRIMARY KEY (project_id), CONSTRAINT projects_users_fk FOREIGN KEY (creator) REFERENCES users (username) ON DELETE CASCADE ) SET NULL will take the value in the child table and get rid of it. What you are left with is NULL. This means that we have an orphaned child. The first thought you might have is that it is a bad thing to have an orphaned child, but in databases that is not always so. In our application if we had it set to SET NULL, when a user account gets deleted the projects would remain in existence they would just lack a creator. This might be a good thing if you are concerned about the long term survival of a project, this might be the route you want to go. It ultimately depends on the application purpose. If you don't like CASCADE or SET NULL, you can leave the entire ON DELETE statement and just have Oracle throw an error when a parent is deleted. As for us, we are going to use ON DELETE CASCADE. We need to use this with extreme caution. If you are not careful, someday you will run a delete a row and that will cascade through you database deleting a bunch of stuff you didn't want to delete. Stuff happens, so make sure you back up your database every once in eternity. Now, in the last video we started with a database design that had three tables. We've only created two in this video. In the next video we are going to create the next one, which is a little special. Then we'll finish things up by adding some indexes. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me on Patreon! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 20108 Caleb Curry
Delete duplicate rows using subquery in Sql server
 
03:56
To delete duplicate rows in a table using subquery in sql server.
Views: 783 surya avvaru
How To Delete Duplicate Rows In MySQL phpMyAdmin 4 7 9
 
03:04
#rowsdeleteduplicate #mysqldeleterowsduplicate Mysql phpmyadmin table delete the duplicate rows using inner join statement
Sql Server Interview Question And Answer Part 18(Reverse Delete duplicate)
 
07:21
How to delete duplicate records when duplicate values are based on multiple columns
Views: 1333 SS UNITECH
how to remove duplicates form a table in oracle
 
02:43
removing of duplicates using sql querries
Views: 143 informatica
Delete duplicate rows in SQL Server
 
07:14
How to fin and delete duplicate rows in SQL Server?
Views: 32 Sai Kumar Reddy
Row Number function in SQL Server
 
07:24
sql server row_number example sql server row number by partition sql server row_number over partition by order by In this video we will discuss Row_Number function in SQL Server. This is continuation to Part 108. Please watch Part 108 from SQL Server tutorial before proceeding. Row_Number function Introduced in SQL Server 2005 Returns the sequential number of a row starting at 1 ORDER BY clause is required PARTITION BY clause is optional When the data is partitioned, row number is reset to 1 when the partition changes Syntax : ROW_NUMBER() OVER (ORDER BY Col1, Col2) Row_Number function without PARTITION BY : In this example, data is not partitioned, so ROW_NUMBER will provide a consecutive numbering for all the rows in the table based on the order of rows imposed by the ORDER BY clause. SELECT Name, Gender, Salary, ROW_NUMBER() OVER (ORDER BY Gender) AS RowNumber FROM Employees Please note : If ORDER BY clause is not specified you will get the following error The function 'ROW_NUMBER' must have an OVER clause with ORDER BY Row_Number function with PARTITION BY : In this example, data is partitioned by Gender, so ROW_NUMBER will provide a consecutive numbering only for the rows with in a parttion. When the partition changes the row number is reset to 1. SELECT Name, Gender, Salary, ROW_NUMBER() OVER (PARTITION BY Gender ORDER BY Gender) AS RowNumber FROM Employees Use case for Row_Number function : Deleting all duplicate rows except one from a sql server table. Discussed in detail in Part 4 of SQL Server Interview Questions and Answers video series. Text version of the video http://csharp-video-tutorials.blogspot.com/2015/09/rownumber-function-in-sql-server.html Slides http://csharp-video-tutorials.blogspot.com/2015/09/rownumber-function-in-sql-server_30.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 92708 kudvenkat
Subscriber Comments Reply Video 11 Find and Delete Duplicate Routes
 
08:13
Subscriber Comments Reply Video 11 Find and Delete Duplicate Routes Click here to subscribe to my youtube channel http://www.youtube.com/channel/UCBt6VrxAIb5jLh9HLDcdwtQ?sub_confirmation=1 Oracle Interview questions and Answers at https://www.youtube.com/playlist?list=PLb1qVSx1k1Vr0v4wVyvT3GEuA0J0M4xBm Oracle 18C New features at https://www.youtube.com/playlist?list=PLb1qVSx1k1Vqe06V1tIBcvnslMPWX69bW Oracle 12C New features at https://www.youtube.com/playlist?list=PLb1qVSx1k1VqM1u2IHWzZIgziqejl6wx- Oracle PLSQL records and collections at https://www.youtube.com/playlist?list=PLb1qVSx1k1VpAFTXopXvAh_D3PLcTntdm
Views: 362 Siva Academy