大约有 7,500 项符合查询结果(耗时:0.0317秒) [XML]

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Inheritance vs. Aggregation [closed]

...e functionality of the original class, is to split the original class in a root class and a sub class. And let the new class inherit from the root class. But you should take care with this, not to create an illogical separation. Lets add an example. We have a class 'Dog' with methods: 'Eat', 'Walk'...
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Why do we use arrays instead of other data structures?

...ss it, because I don't know where it is in memory. All I know is where the root (P1) is, so instead I have to start at P1, and follow each pointer to the desired node. This is a O(N) look up time (The look up cost increases as each element is added). It is much more expensive to get to P1000 compa...
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How many threads can a Java VM support?

...ogram which spawns 25,000 threads and all those threads write some data in MySql database at regular interval of 2 seconds. I ran this program with 10,000 threads for 30 minutes continuously then also my system was stable and I was able to do other normal operations like browsing, opening, closing...
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What are the options for storing hierarchical data in a relational database? [closed]

... Columns: one for each lineage level, refers to all the parents up to the root, levels below the current items' level are set to 0 (or NULL) There is a fixed limit to how deep the hierarchy can be Cheap ancestors, descendants, level Cheap insert, delete, move of the leaves Expensive insert, delete,...
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How to generate .NET 4.0 classes from xsd?

... 2. Within “XML Schema Explorer” scroll all the way down to find the root/data node. Right click on root/data node and it will show “Generate Sample XML”. If it does not show, it means you are not on the data element node but you are on any of the data definition node. Copy your genera...
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Django: How to manage development and production settings?

... MIDDLEWARE = [...] TEMPLATES = [{...}] ... STATIC_URL = '/static/' STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles') MEDIA_ROOT = os.path.join(BASE_DIR, '/path/') MEDIA_URL = '/path/' Open dev.py and include that stuff which is development specific for example: dev.py: DEBUG = True ALLOWED_HOST...
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Timeout expired. The timeout period elapsed prior to completion of the operation or the server is no

...uts or the connection pool size. You'll need to dive in and figure out the root cause. If you need help resolving that root cause you can post your own question. – Marnix van Valen Jul 28 '14 at 6:36 ...
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Why is Magento so slow? [closed]

...o slow Parts of Magento use an EAV database system implemented on top of MySQL. This means querying for a single "thing" often means querying multiple rows There's a lot of things behind the scenes (application configuration, system config, layout config, etc.) that involve building up giant XML ...
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git rebase without changing commit timestamps

...so work with: interactive rebase (rebase -i/rebase --interactive) for the root commit (git rebase --root) See "Change timestamps while rebasing git branch". (Original answer, June 2012) You could try, for a non-interactive rebase (see just above: with Git 2.29, Q4 2020, that will work with an int...
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How to tell bash that the line continues on the next line

...st character before the end of line character. Consider this command: mysql -uroot \ -hlocalhost If there is a space after \, the line continuation will not work. The reason is that \ removes the special meaning for the next character which is a space not the invisible line feed cha...