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Difference Between Select and SelectMany
I've been searching the difference between Select and SelectMany but I haven't been able to find a suitable answer. I need to learn the difference when using LINQ To SQL but all I've found are standard array examples.
...
Where can I get Google developer key
...velopers Console interface was overhauled again. For the new interface:
Select your project from the toolbar.
Open the "Gallery" using hamburger menu icon on the left side of the toolbar and select 'API Manager'.
Click 'Credentials' in the left-hand navigation.
Alternatively, you can click 'Sw...
What's the difference between RANK() and DENSE_RANK() functions in oracle?
...s a simple test script you can play with to see what happens:
with q as (
select 10 deptno, 'rrr' empname, 10000.00 sal from dual union all
select 11, 'nnn', 20000.00 from dual union all
select 11, 'mmm', 5000.00 from dual union all
select 12, 'kkk', 30000 from dual union all
select 10, 'fff', 4000...
Insert new column into table in sqlite?
... populate it with the old data:
INSERT INTO {tableName} (name, qty, rate) SELECT name, qty, rate FROM TempOldTable;
Then delete the old table:
DROP TABLE TempOldTable;
I'd much prefer the second option, as it will allow you to completely rename everything if need be.
...
Execute Insert command and return inserted Id in Sql
...md=new SqlCommand("INSERT INTO Mem_Basic(Mem_Na,Mem_Occ) VALUES(@na,@occ);SELECT SCOPE_IDENTITY();",con))
{
cmd.Parameters.AddWithValue("@na", Mem_NA);
cmd.Parameters.AddWithValue("@occ", Mem_Occ);
con.Open();
int modified = Convert.ToInt32(cmd.ExecuteScalar());...
how to check the dtype of a column in python pandas
...know this is a bit of an old thread but with pandas 19.02, you can do:
df.select_dtypes(include=['float64']).apply(your_function)
df.select_dtypes(exclude=['string','object']).apply(your_other_function)
http://pandas.pydata.org/pandas-docs/version/0.19.2/generated/pandas.DataFrame.select_dtypes.h...
SQL Call Stored Procedure for each Row without using a cursor
...rate over all customers
WHILE (1 = 1)
BEGIN
-- Get next customerId
SELECT TOP 1 @CustomerID = CustomerID
FROM Sales.Customer
WHERE CustomerID > @CustomerId
ORDER BY CustomerID
-- Exit loop if no more customers
IF @@ROWCOUNT = 0 BREAK;
-- call your sproc
EXEC dbo.YOURSPROC...
Cannot simply use PostgreSQL table name (“relation does not exist”)
....
In other words, the following fails:
CREATE TABLE "SF_Bands" ( ... );
SELECT * FROM sf_bands; -- ERROR!
Use double-quotes to delimit identifiers so you can use the specific mixed-case spelling as the table is defined.
SELECT * FROM "SF_Bands";
Re your comment, you can add a schema to th...
Save PL/pgSQL output from PostgreSQL to a CSV file
...e or automate, you can use Postgresql's built in COPY command. e.g.
Copy (Select * From foo) To '/tmp/test.csv' With CSV DELIMITER ',' HEADER;
This approach runs entirely on the remote server - it can't write to your local PC. It also needs to be run as a Postgres "superuser" (normally called "ro...
Best way to work with dates in Android SQLite [closed]
...ing (that is newest date goes first):
public static final String QUERY = "SELECT table._id, table.dateCol FROM table ORDER BY table.dateCol DESC";
//...
Cursor cursor = rawQuery(QUERY, null);
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
// Process results
}
Al...