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Is it possible to modify variable in python that is in outer, but not global, scope?
...esides the global
(module) scope.
For python 2, I usually just use a mutable object (like a list, or dict), and mutate the value instead of reassign.
example:
def foo():
a = []
def bar():
a.append(1)
bar()
bar()
print a
foo()
Outputs:
[1, 1]
...
SQL Server IN vs. EXISTS Performance
... test case does not mean that the optimizer will do the exact same plan on tables with different statistics. This might lead someone to think the answer is partial - but the nonexistence of multiple semijoin operators is fact. Maybe I'll find a list somewhere and link it.
– Geo...
How to store a dataframe using Pandas
...and read_pickle respectively).
Another popular choice is to use HDF5 (pytables) which offers very fast access times for large datasets:
store = HDFStore('store.h5')
store['df'] = df # save it
store['df'] # load it
More advanced strategies are discussed in the cookbook.
Since 0.13 there's...
How to override !important?
...ate. However, on my calendar page, the original CSS has the height of each table cell set with the !important declaration:
...
MySQL复制的概述、安装、故障、技巧、工具 - 数据库(内核) - 清泛网 - 专注...
...--master-data=1 > data.sql
注:master-data选项缺省会打开lock-all-tables,并写入CHANGE MASTER TO语句。
如果数据库使用的是InnoDB表类型的话,则应该使用single-transcation:
shell> mysqldump --all-databases --single-transaction --master-data=1 > data.sql
有了...
Code-first vs Model/Database-first [closed]
... unique index on a field or you can not delete hierarchical data in a tree table for this you need a CTE using the context.Table.SqlQuery("select..."). Model/Database first do not have these drawbacks.
– Elisabeth
Jan 31 '13 at 13:51
...
JavaScript for…in vs for
...uff with o[key]
Unless you have earth shattering reasons, stick to the established pattern of usage.
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jquery get all form elements: input, textarea & select
...on, sometimes this differs from children such as when the form tag is in a table and is not closed.
var summary = [];
$('form').each(function () {
summary.push('Form ' + this.id + ' has ' + $(this).find(':input').length + ' child(ren).');
summary.push('Form ' + this.id + ' has ' + th...
How to read contacts on Android 2.0
...e amount of data that is returned.
String key, value, phoneNumber;
Hashtable contactPhoneInfo = new Hashtable<String, String>();
Uri phoneUri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
String [] PHONES_PROJECTION = new String[] { ContactsContract.CommonDataKinds.Phone.NUMBER ...
Create a custom View by inflating a layout?
...u are using a bit of xml repeatedly. Suppose, for example, that you have a table that you wish to create a table row for each entry in a list. You've set up some xml:
In my_table_row.xml:
<?xml version="1.0" encoding="utf-8"?>
<TableRow xmlns:android="http://schemas.android.com/apk/res/an...