大约有 15,480 项符合查询结果(耗时:0.0331秒) [XML]

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Efficient SQL test query or validation query that will work across all (or most) databases

Many database connection pooling libraries provide the ability to test their SQL connections for idleness. For example, the JDBC pooling library c3p0 has a property called preferredTestQuery , which gets executed on the connection at configured intervals. Similarly, Apache Commons DBCP has valid...
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Handling colon in element ID with jQuery

We are not able to access the div element with ID "test: abc" in JS code using jQuery. 9 Answers ...
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What’s the difference between ScalaTest and Scala Specs unit test frameworks?

Both are BDD (Behavior Driven Development) capable unit test frameworks for Scala written in Scala. And Specs is built upon may also involve the ScalaTest framework. But what does Specs offer ScalaTest doesn't? What are the differences? ...
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Plotting two variables as lines using ggplot2 on the same graph

...all number of variables, you can build the plot manually yourself: ggplot(test_data, aes(date)) + geom_line(aes(y = var0, colour = "var0")) + geom_line(aes(y = var1, colour = "var1")) share | ...
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Test if a variable is set in bash when using “set -o nounset”

... echo 'empty but defined' else echo 'unset' fi } Test: $ unset WHATEVER $ check unset $ WHATEVER= $ check empty but defined $ WHATEVER=' ' $ check not empty share | imp...
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Delete local Git branches after deleting them on the remote repo

...es the delete. For example: someUsr@someHost:~/repo$ git branch -a basic-testing integration-for-tests * master origin playground-for-tests test-services remotes/origin/HEAD -> origin/master remotes/origin/basic-testing remotes/origin/master remotes/origin/test-services someUsr@someHost:~/repo...
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Is null check needed before calling instanceof?

...y good question indeed. I just tried for myself. public class IsInstanceOfTest { public static void main(final String[] args) { String s; s = ""; System.out.println((s instanceof String)); System.out.println(String.class.isInstance(s)); s = null; ...
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PostgreSQL: Difference between text and varchar (character varying)

...er varchar – because it has distinct name The article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provi...
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Fastest way to determine if an integer is between two integers (inclusive) with known sets of values

...re a faster way than x >= start && x <= end in C or C++ to test if an integer is between two integers? 6 An...
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When to use setAttribute vs .attribute= in JavaScript?

...use setAttribute for non-standard attributes. Example: node.className = 'test'; // works node.frameborder = '0'; // doesn't work - non standard attribute node.setAttribute('frameborder', '0'); // works share | ...