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Why does ReSharper want to use 'var' for everything?
...Dictionary<int,bool>>>> q = from t in d where t.Key == null select t; // OMG!
//vs.
var q = from t in d where t.Key == null select t;
// I simply want the first string, so the last version seems fine.
q.First().Key;
You must use var when there's an anonymous ty...
How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...t have to have a placeholder for it in the Insert statement. Then a simple select * into the target table auto populated this column. Here are the two SQL statements that I used on PostgreSQL 9.6.4.
ALTER TABLE target ADD COLUMN some_column SERIAL;
INSERT INTO target SELECT * from source;
...
What to do on TransactionTooLargeException
...and application?
Using intents to share huge data, (for example, the user selects huge number of files from gallery share press share, the URIs of the selected files will be transferred using intents)
receiving bitmap files from service
waiting for android to respond back with huge data (for exampl...
Is there a use-case for singletons with database access in PHP?
...all one needs to maintain multiple database connections, multiple database selections, multiple database queries, multiple result sets in a given singleton is just keeping them in variables/arrays in the singleton as long as they are needed. This can be as simple as keeping them in arrays, though yo...
Why does Hibernate require no argument constructor?
...please look at my problem How to write HQL JOIN query for multiple table's selected Columns using Constructor In The Select Clause
– Shantaram Tupe
Dec 9 '17 at 9:33
...
Convert list of dictionaries to a pandas DataFrame
...o extract only the 0th and 2nd rows from data2 above, you can use:
rows_to_select = {0, 2}
for i in reversed(range(len(data2))):
if i not in rows_to_select:
del data2[i]
pd.DataFrame(data2)
# pd.DataFrame.from_dict(data2)
# pd.DataFrame.from_records(data2)
A B C D E
0 5...
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
...ction table
Example queries:
-- Getting all students for a class:
SELECT s.student_id, last_name
FROM student_classes sc
INNER JOIN students s ON s.student_id = sc.student_id
WHERE sc.class_id = X
-- Getting all classes for a student:
SELECT c.class_id, name
FROM s...
How do you use the Immediate Window in Visual Studio?
...tMessage()
"hello"
A very common way to see the value of a method is to select the method name of a class and do a ‘Add Watch’ so that you can see its current value in the Watch window. However, once again, the object needs to be instantiated and in scope for a valid value to be displayed. ...
Postgres: “ERROR: cached plan must not change result type”
...ng this error.
My application opened a database connection and prepared a SELECT statement for execution.
Meanwhile, another script was modifying the database table, changing the data type of one of the columns being returned in the above SELECT statement.
I resolved this by restarting the applic...
Changing the size of a column referenced by a schema-bound view in SQL Server
...ethod. not just the return on the search process.
view the table class
select * from class
change the length of the columns FacID (seen as "faci") and classnumber (seen as "classnu") to fit the whole labels.
alter table class modify facid varchar (5);
alter table class modify classnumber v...