大约有 47,000 项符合查询结果（耗时：0.0497秒） [XML]
How to re-create database for Entity Framework?
... losing data, I just want to be able to start fresh, recreate the database and start using Code-First migrations.
7 Answer...
What is SYSNAME data type in SQL Server?
...est. It is mainly used by Microsoft when building the internal sys tables and stored procedures etc within SQL Server.
For example, by executing Exec sp_help 'sys.tables' you will see that the column name is defined as sysname this is because the value of this is actually an object in itself (a ta...
How do I convert between big-endian and little-endian values in C++?
How do I convert between big-endian and little-endian values in C++?
31 Answers
31
...
Dashed line border around UIView
...
You can set the border with this pattern using Layer and Bezier path like below examples.
Objective-C
CAShapeLayer *yourViewBorder = [CAShapeLayer layer];
yourViewBorder.strokeColor = [UIColor blackColor].CGColor;
yourViewBorder.fillColor = nil;
yourViewBorder.lineDashPattern...
How to serialize SqlAlchemy result to JSON?
... {}
for field in [x for x in dir(obj) if not x.startswith('_') and x != 'metadata']:
data = obj.__getattribute__(field)
try:
json.dumps(data) # this will fail on non-encodable values, like other classes
fields[field]...
How to create new tmux session if none exists
...session (start the server, read the config file, issue the new-session command) and attach to that.
share
|
improve this answer
|
follow
|
...
Count the number of occurrences of a character in a string in Javascript
...a regular expression literal if you know what you are searching for beforehand, if not you can use the RegExp constructor, and pass in the g flag as an argument.
match returns null with no results thus the || []
The original answer I made in 2009 is below. It creates an array unnecessarily, but us...
What's wrong with nullable columns in composite primary keys?
...keys is not clean relational database design.
If there are two entities A and B where A can optionally be related to B, the clean solution is to create a resolution table (let's say AB). That table would link A with B: If there is a relationship then it would contain a record, if there isn't then i...
What is the fastest or most elegant way to compute a set difference using Javascript arrays?
Let A and B be two sets. I'm looking for really fast or elegant ways to compute the set difference ( A - B or A \B , depending on your preference) between them. The two sets are stored and manipulated as Javascript arrays, as the title says.
...
Change type of varchar field to integer: “cannot be cast automatically to type integer”
I have a small table and a certain field contains the type " character varying ". I'm trying to change it to " Integer " but it gives an error that casting is not possible.
...