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Fast way to discover the row count of a table in PostgreSQL
...of rows due to the nature of MVCC. There is a way to speed this up dramatically if the count does not have to be exact like it seems to be in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like ...
Better way to cast object to int
... to signify a Nullable<int>. The "as" operator works like Convert.To____(), but think TryParse() rather than Parse(): it returns null rather than throwing an exception if the conversion fails.
Of these, I would prefer (int) if the object really is just a boxed integer. Otherwise use Conver...
Control cannot fall through from one case label
...is present. I have the following code. But I am getting a "Control cannot fall through from one case label" error.
8 Answer...
How to set session timeout in web.config
...how to set session timeout value for in-process session for an ASP.Net web application.
5 Answers
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Reactjs convert html string to jsx
...se the dangerouslySetInnerHTML property:
<td dangerouslySetInnerHTML={{__html: this.state.actions}} />
React forces this intentionally-cumbersome syntax so that you don't accidentally render text as HTML and introduce XSS bugs.
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What is the maximum possible length of a .NET string?
...st you could do is 1,073,741,823, but you're not likely to ever be able to allocate that on a 32-bit machine.
This is one of those situations where "If you have to ask, you're probably doing something wrong."
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What is a .pid file and what does it contain?
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Pidfile contains pid of a process. It is a convention allowing long running processes to be more self-aware. Server process can inspect it to stop itself, or have heuristic that its other instance is already running. Pidfiles can also be used to conventiently kill risk manually,...
How do you set a default value for a MySQL Datetime column?
... need to ALWAYS specify a value for this column or the value will automatically reset itself to "now()" on update. This means that if you do not want the value to change, your UPDATE statement must contain "[your column name] = [your column name]" (or some other value) or the value will become "now(...
What is the difference between JavaConverters and JavaConversions in Scala?
...eating wrappers that implement either the Scala interface and forward the calls to the underlying Java collection, or the Java interface, forwarding the calls to the underlying Scala collection.
JavaConverters uses the pimp-my-library pattern to “add” the asScala method to the Java collections ...
Can you control how an SVG's stroke-width is drawn?
...inside|outside possible values). This property may make it into UAs eventually.
Edit 3: Amusingly and dissapointingly, the SVG working group has removed stroke-alignment from SVG 2. You can see some of the concerns described after the prose here.
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