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MySQL ON vs USING?
...fferences are noteworthy:
ON is the more general of the two. One can join tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exac...
How do I find which transaction is causing a “Waiting for table metadata lock” state?
I am trying to perform some DDL on a table and SHOW PROCESSLIST results in a " Waiting for table metadata lock " message.
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Having both a Created and Last Updated timestamp columns in MySQL 4.0
I have the following table schema;
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UITableViewCell, show delete button on swipe
How do I get the delete button to show when swiping on a UITableViewCell ? The event is never raised and the delete button never appears.
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Simple way to convert datarow array to datatable
I want to convert a DataRow array into DataTable ... What is the simplest way to do this?
14 Answers
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How To: Best way to draw table in console app (C#)
... of data changing in very fast intervals.
I want to display that data as a table in console app. f.ex:
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Delete duplicate records in SQL Server?
Consider a column named EmployeeName table Employee . The goal is to delete repeated records, based on the EmployeeName field.
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When increasing the size of VARCHAR column on a large table could there be any problems?
...er 2008 and I need to make a VARCHAR field bigger, from (200 to 1200) on a table with about 500k rows. What I need to know is if there are any issues I have not considered.
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Difference Between Schema / Database in MySQL
...racle Database product, a schema represents only a part of a database: the tables and other objects owned by a single user.
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When and why are database joins expensive?
...nality when (if) they set up indexes.
It is important to understand that table scans (examination of every row in a table in the course of producing a join) are rare in practice. A query optimiser will choose a table scan only when one or more of the following holds.
There are fewer than 200 row...