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Hibernate throws MultipleBagFetchException - cannot simultaneously fetch multiple bags
...Many(mappedBy="parent", fetch=FetchType.EAGER)
@Fetch(value = FetchMode.SUBSELECT)
private List<Child> childs;
This should fix the issue, related to Hibernate bug HHH-1718
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How do I create a list of random numbers without duplicates?
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This will return a list of 10 numbers selected from the range 0 to 99, without duplicates.
import random
random.sample(range(100), 10)
With reference to your specific code example, you probably want to read all the lines from the file once and then select rand...
Apply multiple functions to multiple groupby columns
... group. When aggregating, g will be a Series. Passing g.index to df.ix[] selects the current group from df. I then test if column C is less than 0.5. The returned boolean series is passed to g[] which selects only those rows meeting the criteria.
In [95]: cust = lambda g: g[df.loc[g.index]['C']...
How to merge a list of lists with same type of items to a single list of items?
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Use the SelectMany extension method
list = listOfList.SelectMany(x => x).ToList();
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Do I have to guard against SQL injection if I used a dropdown?
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$size = filter_input(INPUT_POST, "size", FILTER_VALIDATE_INT);
echo '<select name="size">';
foreach($sizes as $i => $s) {
echo '<option value="' . $i . '"' . ($i == $size ? ' selected' : '') . '>' . $s . '</option>';
}
echo '</select>';
Then you can use $size in yo...
How to deal with SettingWithCopyWarning in Pandas?
...owing, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2]['B'] = new_val # new_val not set in df
The warning offers a suggestion to rewrite as follows:
df.loc[df['A'] > 2, 'B'] =...
Why use a READ UNCOMMITTED isolation level?
...on. This option has the same effect as setting NOLOCK on all tables in all SELECT statements in a transaction. This is the least restrictive of the four isolation levels.
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NSInvalidUnarchiveOperationException: Could not instantiate class named NSLayoutConstraint
...the first tab in the left hand side inspector, when you have File's owner) selected.
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Rails Object to hash
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Works with joins and select, Person.joins(:address).select("addresses.street, persons.name").find_by_id(id).attributes, will return { street: "", name: "" }
– fangxing
Jun 15 '17 at 2:29
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How do I perform the SQL Join equivalent in MongoDB?
...background as well, I would appreciate MongoDB taking a 'result set' (with selected returned fields) as input for a new query in one go, much like nested queries in SQL
– Stijn Sanders
Nov 26 '10 at 23:17
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