大约有 5,100 项符合查询结果（耗时：0.0206秒） [XML]
Does a foreign key automatically create an index?
...kup a relating table and extract certain rows based on a single value or a range of values.
So it makes good sense to index any columns involved in a FK, but a FK per se is not an index.
Check out Kimberly Tripp's excellent article "When did SQL Server stop putting indexes on Foreign Key columns?"...
How can I parse a YAML file in Python
...rror: 'ascii' codec can't decode byte 0xe7 in position 926: ordinal not in range(128)). I've tried to set yaml.encoding to utf-8 but didn't work as the load method in YAML still uses the ascii_decode. Is this a bug?
– SnwBr
Jan 7 at 17:53
...
How to write inline if statement for print?
...hon doesn't have a trailing if, then why does this work: print [i for i in range(10) if i%2]? I wish they'd allow it outside of comprehensions...
– mbomb007
Sep 26 '15 at 22:13
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How do I split a multi-line string into multiple lines?
...
It is strange that this answer is so upvoted. Hard coding '\n' is a bad idea, but even if you use os.linesep instead of that, you will have issues with windows line ends on Linux and vice versa, etc. Moreover, it is promoting splitli...
Remove specific characters from a string in Python
...hon regular expression documentation:
Characters that are not within a range can be matched by complementing
the set. If the first character of the set is '^', all the characters
that are not in the set will be matched. For example, [^5] will match
any character except '5', and [^^] will m...
How to iterate through SparseArray?
... the documentation states that "keyAt(int index) Given an index in the range 0...size()-1, returns the key from the indexth key-value mapping that this SparseArray stores." so it works fine for me even for the case described by you.
– Ruzanna
Mar 3 '12 at 1...
How does Python manage int and long?
...Arg_Parse*() APIs already accept long ints, as long as they are within the range representable by C ints or longs, so that functions taking C int or long argument won't have to worry about dealing with Python longs.
– cowbert
Nov 16 '18 at 6:30
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Return a “NULL” object if search result not found
...e. You want to return something that might exist. Here are some options, ranging from my least preferred to most preferred:
Return by reference, and signal can-not-find by exception.
Attr& getAttribute(const string& attribute_name) const
{
//search collection
//if found at i
...
Validation failed for one or more entities while saving changes to SQL Server Database using Entity
...text.
It handles DbEntityValidationException, DbUpdateException, datetime2 range errors (MS SQL), and include key of invalid entity in message (useful when savind many entities at one SaveChanges call).
First, override SaveChanges in DbContext class:
public class AppDbContext : DbContext
{
pub...
Style input element to fill remaining width of its container
...ery easy trick is using a CSS calc formula. All modern browsers, IE9, wide range of mobile browsers should support this.
<div style='white-space:nowrap'>
<span style='display:inline-block;width:80px;font-weight:bold'>
<label for='field1'>Field1</label>
</span>
...