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How to search a specific value in all tables (PostgreSQL)?
... at 11:55
Mike Sherrill 'Cat Recall'Mike Sherrill 'Cat Recall'
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Postgresql - change the size of a varchar column to lower length
I have a question about the ALTER TABLE command on a really large table (almost 30 millions rows).
One of its columns is a varchar(255) and I would like to resize it to a varchar(40) .
Basically, I would like to change my column by running the following command:
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Configuring Log4j Loggers Programmatically
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You can add/remove Appender programmatically to Log4j:
ConsoleAppender console = new ConsoleAppender(); //create appender
//configure the appender
String PATTERN = "%d [%p|%c|%C{1}] %m%n";
console.setLayout(new PatternLayout(PATTERN));
console.setThresh...
Should I instantiate instance variables on declaration or in the constructor?
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There is no difference - the instance variable initialization is actually put in the constructor(s) by the compiler.
The first variant is more readable.
You can't have exception handling with the first variant.
There is additionally the initialization block, which is as well put in the constru...
MySQL, update multiple tables with one query
...ookID is very important, without it The Books table update would happen to all rows and not only for the row with the specified id. Some lessons are learned the hard way, this one was learned in the terrifing way.
– nheimann1
Mar 24 '15 at 15:06
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Removing all unused references from a project in Visual Studio projects
... wondered if it possible within various Visual Studio versions to automatically remove all references from a project that were never been used?
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Replace spaces with dashes and make all letters lower-case
...games"
Notice the g flag on the RegExp, it will make the replacement globally within the string, if it's not used, only the first occurrence will be replaced, and also, that RegExp will match one or more white-space characters.
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On duplicate key ignore? [duplicate]
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Would suggest NOT using INSERT IGNORE as it ignores ALL errors (ie its a sloppy global ignore).
Instead, since in your example tag is the unique key, use:
INSERT INTO table_tags (tag) VALUES ('tag_a'),('tab_b'),('tag_c') ON DUPLICATE KEY UPDATE tag=tag;
on duplicate key pro...