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Topics: mysql

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• How to find duplicate records in MySQL across multiple columns

  

  By sarahkim : 09 November 2009 - 04:57 PM

  We have a MySQL 4 table of authors with separate first name and last name columns. I wanted to get a list of all possible duplicates (authors in the table with the exact same first name and last name...

  Tags:

  • mysql
  • duplicates

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  0Comments

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• How to Use SQL to Search for Keywords Without the LIKE Operator

  

  By andr3w : 27 October 2009 - 10:06 PM

  You can do a simple keyword search using the LIKE operator. Unfortunately, this can be slow. Fortunately, an efficient keyword search is available in many systems.Often you must store ...

  Tags:

  • sql server
  • postgresql
  • mysql
  • LIKE
  • sql
  • oracle
  • databases
  • data

  1Vote

  0Comments

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• How to get a random sample in SQL

  

  By odewahn1 : 15 October 2009 - 06:36 AM

  It can be a real pain to develop and test queries against really big tables. So, rather than query the entire table, you can use a simple trick to select a random sample (a smaller subset). Here...

  Tags:

  • mysql
  • sql
  • databases
  • hacks

  0Votes

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• How to Add and Delete users to a Web Database using PHP and MySql

  

  By MikeH : 02 October 2009 - 11:50 AM

  So if you want to learn how to add and delete users to a Web Database using PHP and Mysql, consider reading this chapter out of: Learning PHP, MySQL, and Javascript, 1st Edition I would no...

  Tags:

  • php
  • mysql
  • tables

  2Votes

  0Comments

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• How to use events to schedule database actions in MySQL

  

  By pauldubois : 14 September 2009 - 10:49 AM

  If you want to set up a database operation that runs periodically without user intervention, create an event that executes according to a schedule.As of MySQL 5.1, one of the capabilities...

  Tags:

  • mysql
  • events
  • schedule
  • mark

  0Votes

  0Comments

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• How to use a trigger to log changes to a table in MySQL

  

  By pauldubois : 14 September 2009 - 10:10 AM

  If you have a table that maintains current values of items that you track (such as auctions being bid on), but you’d also like to maintain a journal (or history) of changes to...

  Tags:

  • log
  • triggers
  • mysql
  • table

  0Votes

  0Comments

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• How to simulate TIMESTAMP properties for other date and time types in MySQL

  

  By pauldubois : 14 September 2009 - 10:02 AM

  The TIMESTAMP data type provides auto-initialization and auto-update properties. If you would like to use these properties for other temporal data types, but the other ...

  Tags:

  • mysql
  • timestamp
  • time
  • date
  • trigger

  0Votes

  0Comments

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• How to use a trigger to define dynamic default column values in MySQL

  

  By pauldubois : 14 September 2009 - 09:46 AM

  If a column in a table needs to be initialized to a nonconstant value, but MySQL allows only constant default values, use a BEFORE INSERT trigger. This e...

  Tags:

  • before insert
  • triggers
  • mysql
  • timestamp

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• How to create compound-statement objects in MySQL

  

  By pauldubois : 14 September 2009 - 09:10 AM

  If you want to define a stored routine, a trigger, or an event, but its body contains instances of the ; statement terminator, redefine the mysql statement terminator w...

  Tags:

  • triggers
  • stored procdeures
  • delimiter
  • compound-statement
  • mysql

  0Votes

  0Comments

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• How to use sequence generators as counters in MySQL

  

  By pauldubois : 11 September 2009 - 06:04 PM

  If you’re interested only in counting events, use a sequence-generation mechanism that uses just one row per counter.AUTO_INCREMENTcolumns are useful for generating sequences across a ...

  Tags:

  • ruby
  • python
  • counter
  • sequence generator
  • sql
  • mysql
  • java

  0Votes

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