大约有 40,000 项符合查询结果（耗时：0.0342秒） [XML]
Python's json module, converts int dictionary keys to strings
...e.
In Python (and apparently in Lua) the keys to a mapping (dictionary or table, respectively) are object references. In Python they must be immutable types, or they must be objects which implement a __hash__ method. (The Lua docs suggest that it automatically uses the object's ID as a hash/key ...
Working with huge files in VIM
...s a 300GB mysql dump and I wanted to get rid of the DROP and change CREATE TABLE to CREATE TABLE IF NOT EXISTS so didn't want to run two invocations of sed. I wrote this quick Ruby script to dupe the file with those changes:
#!/usr/bin/env ruby
matchers={
%q/^CREATE TABLE `foo`/ => %q/CREA...
What's the difference between belongs_to and has_one?
...oreign key is. We can say that a User "has" a Profile because the profiles table has a user_id column. If there was a column called profile_id on the users table, however, we would say that a Profile has a User, and the belongs_to/has_one locations would be swapped.
here is a more detailed explanat...
'console' is undefined error for Internet Explorer
...le.debug
*
* Chrome 41.0.2272.118: debug,error,info,log,warn,dir,dirxml,table,trace,assert,count,markTimeline,profile,profileEnd,time,timeEnd,timeStamp,timeline,timelineEnd,group,groupCollapsed,groupEnd,clear
* Firefox 37.0.1: log,info,warn,error,exception,debug,table,trace,dir,group,groupCollap...
How do I find duplicate values in a table in Oracle?
...or a given column and the count of their occurrences in an Oracle database table?
13 Answers
...
How to hide columns in HTML table?
I have created a table in ASPX. I want to hide one of the columns based on the requirement but there is no attribute like visible in the HTML table building. How can I solve my problem?
...
Add new column with foreign key constraint in one command
...to add the column and the foreign key constraint using two separate ALTER TABLE commands:
12 Answers
...
How to list all users in a Linux group?
...
Unfortunately, there is no good, portable way to do this that I know of. If you attempt to parse /etc/group, as others are suggesting, you will miss users who have that group as their primary group and anyone who has been added to that group via a mechanism ot...
How to change owner of PostgreSql database?
...
@mArtinko5MB: Also impossible, ALTER TABLE doesn't DROP the table. Show us your SQL, something is badly broken in your statements.
– Frank Heikens
Oct 24 '13 at 13:24
...
Why is LINQ JOIN so much faster than linking with WHERE?
...nce they work directly in memory (Linq to DataSet)
The query with multiple tables and a Where condition actually performs a cartesian product of all the tables, then filters the rows that satisfy the condition. This means the Where condition is evaluated for each combination of rows (n1 * n2 * n3 * ...