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How to make custom error pages work in ASP.NET MVC 4
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<section id="Page">
<div class="col-xs-12 well">
<table cellspacing="5" cellpadding="3" style="background-color:#fff;width:100%;" class="table-responsive">
<tbody>
<tr>
<td valign="top" align="left" id="tableProps">
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Long press on UITableView
I would like to handle a long press on a UITableViewCell to print a "quick access menu".
Did someone already do this?
10...
SQL Server reports 'Invalid column name', but the column is present and the query works through mana
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I suspect that you have two tables with the same name. One is owned by the schema 'dbo' (dbo.PerfDiag), and the other is owned by the default schema of the account used to connect to SQL Server (something like userid.PerfDiag).
When you have an unquali...
How to read a CSV file into a .NET Datatable
How can I load a CSV file into a System.Data.DataTable , creating the datatable based on the CSV file?
22 Answers
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How to split a comma-separated value to columns
I have a table like this
36 Answers
36
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How do I modify a MySQL column to allow NULL?
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You want the following:
ALTER TABLE mytable MODIFY mycolumn VARCHAR(255);
Columns are nullable by default. As long as the column is not declared UNIQUE or NOT NULL, there shouldn't be any problems.
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Best explanation for languages without null
...f why null is undesirable is that meaningless states should not be representable.
Suppose I'm modeling a door. It can be in one of three states: open, shut but unlocked, and shut and locked. Now I could model it along the lines of
class Door
private bool isShut
private bool isLocked
an...
Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...rticularly user friendly. For instance, I'm displaying a datagrid of a sql table, and I'd like the users to be able to see/edit true or false, not 1 or 0.
– Charles Clayton
Jul 17 '15 at 16:04
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How do I catch a PHP fatal (`E_ERROR`) error?
...ace = print_r( debug_backtrace( false ), true );
$content = "
<table>
<thead><th>Item</th><th>Description</th></thead>
<tbody>
<tr>
<th>Error</th>
<td><pre&...
Numbering rows within groups in a data frame
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Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
library(plyr)
ddply(df, .(cat), mutate, id = seq_along(val))
or:
library(dplyr)
df %>% group_by(cat) %>% mutate(id = row_number())
or (the most memor...