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Dynamically select data frame columns using $ and a character value
...and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , nether of these work
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Django select only rows with duplicate field values
...ithout this, the subquery fails. The extra values tricks the ORM into only selecting the name column for the subquery.
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How to check all checkboxes using jQuery?
...});
Html should be :
Single check box on checked three checkbox will be select and deselect.
<input type="checkbox" name="checkedAll" id="checkedAll" />
<input type="checkbox" name="checkAll" class="checkSingle" />
<input type="checkbox" name="checkAll" class="checkSingle" />
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What is the use of ByteBuffer in Java? [closed]
...s;
Relative bulk get methods that transfer contiguous sequences of bytes from this buffer into an array;
Relative bulk put methods that transfer contiguous sequences of bytes from a byte array or some other byte buffer into this buffer;
Absolute and relative get and put methods that read and w...
How do I create a SQL table under a different schema?
...er 2008
1. Navigate to Security > Schemas
2. Right click on Schemas and select New Schema
3. Complete the details in the General tab for the new schema. Like, the schema name is "MySchema" and the schema owner is "Admin".
4. Add users to the schema as required and set their permissions:
5. Add an...
Replacing NULL with 0 in a SQL server query
...u want to replace a possibly null column with something else, use IsNull.
SELECT ISNULL(myColumn, 0 ) FROM myTable
This will put a 0 in myColumn if it is null in the first place.
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ImportError: No module named Crypto.Cipher
...alenv keeps returning the error listed above. My import statement is just from Crypto.Cipher import AES . I looked for duplicates and you might say that there are some, but I tried the solutions (although most are not even solutions) and nothing worked.
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SQLite UPSERT / UPDATE OR INSERT
... at this code:
INSERT INTO players (id, name, age)
VALUES (
coalesce((select id from players where user_name='steven'),
(select max(id) from drawings) + 1),
32)
The trick is in coalesce. It returns the id of the user 'steven' if any, and otherwise, it returns a new fresh id.
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Entity framework linq query Include() multiple children entities
...ch allows the required depth of eager loading to be specified by providing Select expressions to the appropriate depth:
using System.Data.Entity; // NB!
var company = context.Companies
.Include(co => co.Employees.Select(emp => emp.Employee_Car))
.Inc...
Node.js Error: Cannot find module express
... project directory. So you should copy the file the express module folders from C:\Users\Dmitry\AppData\Roaming\npm\node_modules\ to your project directory as : C:\ChatServer\Server\node_modules. If you do not have a folder named 'node_modules' in your project folder, then create it first and paste ...