大约有 42,000 项符合查询结果（耗时：0.0304秒） [XML]
How to find a table having a specific column in postgresql
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you can query system catalogs:
select c.relname
from pg_class as c
inner join pg_attribute as a on a.attrelid = c.oid
where a.attname = <column name> and c.relkind = 'r'
sql fiddle demo
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Select unique or distinct values from a list in UNIX shell script
I have a ksh script that returns a long list of values, newline separated, and I want to see only the unique/distinct values. It is possible to do this?
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ng-model for `` (with directive DEMO)
...cope.fileread = changeEvent.target.files[0];
// or all selected files:
// scope.fileread = changeEvent.target.files;
});
});
}
}
}]);
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What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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Selecting and manipulating CSS pseudo-elements such as ::before and ::after using jQuery
Is there any way to select/manipulate CSS pseudo-elements such as ::before and ::after (and the old version with one semi-colon) using jQuery?
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What is SQL injection? [duplicate]
...ue for any language), which might be used to handle a user login.
$sql = "SELECT FROM users WHERE username='".$_GET['username']."' AND password='".$_GET['password']."'";
The harm is done when the user enters something like
administrator'; --
... for the username. Without proper encoding the...
Disable Maven warning message - “Selected war files include a WEB-INF/web.xml which will be ignored”
... },
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true,enableSnippets:true
});
}
});
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MYSQL OR vs IN performance
...for future Googlers. Total count of returned results is 7264 out of 10000
SELECT * FROM item WHERE id = 1 OR id = 2 ... id = 10000
This query took 0.1239 seconds
SELECT * FROM item WHERE id IN (1,2,3,...10000)
This query took 0.0433 seconds
IN is 3 times faster than OR
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What is the difference between Views and Materialized Views in Oracle?
... you. The downside of a view is that its performance depends on how good a select statement the view is based on. If the select statement used by the view joins many tables, or uses joins based on non-indexed columns, the view could perform poorly.
Materialized views
They are similar to regular vi...
How do I install Eclipse Marketplace in Eclipse Classic?
...available add the site "Juno - http://download.eclipse.org/releases/juno"
Select and expand general purpose tools
Select and install Marketplace client
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