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MySQL - why not index every field?
...k about index updates were one update trigger all indexes update this is a select all unordered equivalent in time
from this I conclude that you have in this scenario that if you will loose this time is preferable to lose it in a select nor an update because if you will select a field that is not i...
Can a unit test project load the target application's app.config file?
...08 I added the app.config file to the test project as an existing item and selected copy as link in order to make sure it's not duplicated. That way I only have one copy in my solution. With several test projects it comes in really handy!
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What's the difference between TRUNCATE and DELETE in SQL
...tranTest | DELETE FROM tranTest |
| SELECT * FROM tranTest | SELECT * FROM tranTest |
| ROLLBACK | ROLLBACK |
| SELECT * FROM tranTest | SELE...
ASP MVC in IIS 7 results in: HTTP Error 403.14 - Forbidden
...ommand prompt as an Administrator (right click the command prompt icon and select Run as Administrator):
cd \
cd Windows\Microsoft.NET\Framework\v4.xxx.xxx
aspnet_regiis -i
Once it has installed and registered, make sure you application is using an application pool that is set to .NET 4.0.
UPDAT...
This Row already belongs to another table error when trying to add rows?
I have a DataTable which has some rows and I am using the select to filter the rows to get a collection of DataRows which I then loop through using foreach and add it to another DataTable, but it is giving me the error "This Row already belongs to another table". Here is the code:
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Selecting only numeric columns from a data frame
...traightforward, and robust to use on database-back-ended tibbles:
dplyr::select_if(x, is.numeric)
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Ora-00257 错误处理一列 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
.../oracle/.bash_profile
进入ORLACE
sqlplus /as sysdba
SQL> select * from v$log;
GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC
---------- ---------- ---------- ---------- ---------- ---------- ---
STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE#...
Oracle SQL escape character (for a '&')
... table blah (x varchar(20));
insert into blah (x) values ('blah&amp');
select * from blah;
X
--------------------
blah&amp
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Oracle SQL, concatenate multiple columns + add text
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select 'i like' || type_column || ' with' ect....
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Disabled form fields not submitting data [duplicate]
...entioned: READONLY does not work for <input type='checkbox'> and <select>...</select>.
If you have a Form with disabled checkboxes / selects AND need them to be submitted, you can use jQuery:
$('form').submit(function(e) {
$(':disabled').each(function(e) {
$(this).rem...