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INNER JOIN ON vs WHERE clause
...ed is a cartesian product of the tables to which a filter is applied which selects only those rows with joining columns matching.
It's easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STR...
LINQ's Distinct() on a particular property
...
(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)
{
HashSet<TKey> seenKeys = new HashSet<TKey>();
foreach (TSource element in source)
{
if (seenKeys.Add(keySelector(element)))
{
yield return element;
}
...
How do I select the parent form based on which submit button is clicked?
...
You can select the form like this:
$("#submit").click(function(){
var form = $(this).parents('form:first');
...
});
However, it is generally better to attach the event to the submit event of the form itself, as it will tri...
How to select a node using XPath if sibling node has a specific value?
...
Q: How to select a node using XPath if sibling node has a specific value?
Because there are only "XPath Axes" for following-siblings and preceding-siblings, you can use one of them if the position is fixed.
But better:
Look for cc w...
No identities were available - administrator request
...uble click) the new provisioning profile.
In your project's build settings select the NEW provisioning profile (it might have the same name as the old one)
In your project's build settings update your code signing identities (all of them) to the new one if there is one. (The old one was probably exp...
python-pandas and databases like mysql
...a_conn = cx_Oracle.connect('your_connection_string')
df_ora = pd.read_sql('select * from user_objects', con=ora_conn)
print 'loaded dataframe from Oracle. # Records: ', len(df_ora)
ora_conn.close()
And here is the equivalent example for MySQLdb:
import MySQLdb
mysql_cn= MySQLdb.connect(host='...
Is there a way to make ellipsize=“marquee” always scroll?
... was generally very ordinary — except for the fact that it was marked as selected.
One line of code later and I had it working :)
textView.setSelected(true);
This makes sense, given what the Javadoc says:
A view can be selected or not. Note that selection is not the same as focus. Views ar...
How can I calculate the difference between two dates?
...s of time, they do not have any associated time-zone information. When you convert a string to a date using e.g. an NSDateFormatter, the NSDateFormatter converts the time from the configured timezone. Therefore, the number of seconds between two NSDate objects will always be time-zone-agnostic.
Fur...
Non-alphanumeric list order from os.listdir()
...u have to write it yourself:
import re
def sorted_alphanumeric(data):
convert = lambda text: int(text) if text.isdigit() else text.lower()
alphanum_key = lambda key: [ convert(c) for c in re.split('([0-9]+)', key) ]
return sorted(data, key=alphanum_key)
You can now use this function ...
Cleaning `Inf` values from an R dataframe
...ar)
dat %>% rationalize()
Which return a data frame with all Inf are converted to NA.
Timings compared to some above solutions. Code:
library(hablar)
library(data.table)
dat <- data.frame(a = rep(c(1,Inf), 1e6), b = rep(c(Inf,2), 1e6),
c = rep(c('a','b'),1e6),d = rep(c(...