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Rails: How can I set default values in ActiveRecord?
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See Paul Russell's comment on this answer for more details
If you're only selecting a subset of columns for a model (ie; using select in a query like Person.select(:firstname, :lastname).all) you will get a MissingAttributeError if your init method accesses a column that hasn't been included in the...
How to use if-else option in JSTL
...prefix="c" uri="http://www.springframework.org/tags/form"%>
and
<c:select>
<option value="RCV"
${records[0].getDirection() == 'RCV' ? 'selected="true"' : ''}>
<spring:message code="dropdown.Incoming" text="dropdown.Incoming" />
...
How would I skip optional arguments in a function call?
...llowing:
function getData($name, $limit = '50', $page = '1') {
return "Select * FROM books WHERE name = $name AND page = $page limit $limit";
}
echo getData('some name', '', '23'); // won't work as expected
The output will be:
"Select * FROM books WHERE name = some name AND page = 23 limit"
...
app-release-unsigned.apk is not signed
...ettings.
Go to Signing Tab. Add a signing config and fill in information. Select your keychain as well.
Go to Build Type tab. Select release mode and set:
-Debuggable to true.
-Signing Config to the config. (The one you just created).
Sync your gradle. Enjoy!
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Is there a JSON equivalent of XQuery/XPath?
...g
tools including filtering, recursive search, sorting, mapping, range
selection, and flexible expressions with wildcard string comparisons
and various operators.
JSONselect has another point of view on the question (CSS selector-like, rather than XPath) and has a JavaScript implementation.
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“Remote System Explorer Operation” causing freeze for couple of seconds
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Here are the steps:
Click on the Windows > Preferences menu
Select General > Workspace > Build in the tree
Uncheck Use default build order
Select RemoteSystemsTempFiles
Click Remove Project
Click Apply and Close
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facebook: permanent Page Access Token?
...ken.
1. Get User Short-Lived Access Token
Go to the Graph API Explorer.
Select the application you want to get the access token for (in the "Application" drop-down menu, not the "My Apps" menu).
Click "Get Token" > "Get User Access Token".
In the pop-up, under the "Extended Permissions" tab, c...
Nearest neighbors in high-dimensional data?
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First, the number of features (columns) in a data set is not a factor in selecting a distance metric for use in kNN. There are quite a few published studies directed to precisely this question, and the usual bases for comparison are:
the underlying statistical
distribution of your data;
the rel...
What is in your Mathematica tool bag? [closed]
...pplication of Reap and Sow which mimics/extends the behavior of GatherBy:
SelectEquivalents[x_List,f_:Identity, g_:Identity, h_:(#2&)]:=
Reap[Sow[g[#],{f[#]}]&/@x, _, h][[2]];
This allows me to group lists by any criteria and transform them in the process. The way it works is that a c...
When to use single quotes, double quotes, and backticks in MySQL
...ng query will produce different results (or errors) depending on SQL mode:
SELECT "column" FROM table WHERE foo = "bar"
ANSI_QUOTES disabled
The query will select the string literal "column" where column foo is equal to string "bar"
ANSI_QUOTES enabled
The query will select the column column where ...