Chances are that you are hitting on a problem with parameter sniffing. I suggest reading Slow in the Application, Fast in SSMS? by Erland Sommarskog to get a full understanding of the issue (long article but very good).
I think this is what you’re looking for. List<String> columnData = new List<String>(); using(SqlConnection connection = new SqlConnection(“conn_string”)) { connection.Open(); string query = “SELECT Column1 FROM Table1”; using(SqlCommand command = new SqlCommand(query, connection)) { using (SqlDataReader reader = command.ExecuteReader()) { while (reader.Read()) { columnData.Add(reader.GetString(0)); } } } } Not tested, but this should work fine.
You can (should) use CROSS JOIN. Following query will be equivalent to yours: SELECT table1.columnA , table2.columnA FROM table1 CROSS JOIN table2 WHERE table1.columnA = ‘Some value’ or you can even use INNER JOIN with some always true conditon: FROM table1 INNER JOIN table2 ON 1=1
UPDATE public.clean_trips_byobu SET trip_dist = clean_trips.bktp_mt_total FROM public.clean_trips WHERE public.clean_trips.obu_id = clean_trips_byobu.obu_id AND clean_trips.bktp_trip_id = clean_trips_byobu.trip_id; Hope it will work for you.
You can use @@ROWCOUNT server variable immediately after the insert query to check number of affected rows by the insert operation. declare @fName varchar(50) = ‘Abcd’, @lName varchar(50) = ‘Efgh’ INSERT INTO myTbl(fName,lName) values(@fName,@lName) PRINT @@ROWCOUNT –> 0- means no rows affected/nothing inserted –> 1- means your row has been inserted successfully For your requirement, … Read more
You can use following constructs to filter the Date column using either year or month: .filter(extract(‘year’, Foo.Date) == 2012) .filter(extract(‘month’, Foo.Date) == 12) And group_by is also possible: .group_by(sqlalchemy.func.year(Foo.Date), sqlalchemy.func.month(Foo.Date)) Now I haven’t tested it, but I assume that this might be slow because these queries result in full table scans, therefore I suggest you … Read more
That isn’t quite an SQL file, that contains a bunch of MySQL-specific stuff some of which SQLite will accept and some it won’t. We’ll start at the top. You don’t need create database or use with SQLite. If you want to create a database just name it when you run sqlite3 from the command line: … Read more
Apparently the looping construct in SQLite is the WITH RECURSIVE clause. That documentation link has sample count-to-ten code, a Mandelbrot set plotter, and a Sudoku puzzle solver, all in pure SQL. Here’s an SQLite query that computes the Fibonacci sequence to give you a feel for it: sqlite> WITH RECURSIVE …> fibo (curr, next) …> … Read more
You can use migration wizard from MySQL Workbench. Just choose the same local connection in both source and target selection, then change schema name on manual editing step. If nothing appears on manual editing step click next and the source and targets will appear. Click slowly on the source database name and edit to the … Read more
I’m not an SQL tuning expert, but joining hundreds of millions of rows on a VARCHAR field doesn’t sound like a good idea in any database system I know. You could try adding an integer column to each table and computing a hash on the NAME field that should get the possible matches to a … Read more