The message: No data sources are configured to run this SQL and provide advanced code assistance. is a little explicit and IMHO a little unnecessary, because I really think that I don’t need to configure a database for every project in which we have some SQL queries. To handle this message, you have two options: … Read more
You can just use cast it to an integer. It will truncate it, which is equivalent to floor.
In Python 2, you’ll have to explicitly test for the existence using os.path.isfile: if os.path.isfile(db): There is no way to force the sqlite3.connect function to not create the file for you. For those that are using Python 3.4 or newer, you can use the newer URI path feature to set a different mode when opening … Read more
You can calculate the variance in SQL: create table t (row int); insert into t values (1),(2),(3); SELECT AVG((t.row – sub.a) * (t.row – sub.a)) as var from t, (SELECT AVG(row) AS a FROM t) AS sub; 0.666666666666667 However, you still have to calculate the square root to get the standard deviation.
SELECT * FROM users WHERE column LIKE ‘%mystring%’ will do it. LIKE means we’re not doing an exact match (column = value), but doing some more fuzzy matching. “%” is a wildcard character – it matches 0 or more characters, so this is saying “all rows where the column has 0 or more chars followed … Read more
Open the about:telemetry link in Firefox and click scalars tab from the sidebar menu. Alternatively, opening about:telemetry#scalars-tab_search=tab will take you directly to the scalars tab. The browser.engagement.max_concurrent_tab_count key will show the number of tabs active for the session, but does not update when a tab is closed. Instead, if you want to update this value … Read more
The execution time geometrically proportional to the number of rows in each table rather than arithmetically e.g. 3 tables with 10 rows each => 1,000 comparision 3 tables with 10, 10 and 40 rows => 4,000 comparisons 3 tables with 20 rows each => 8,000 comparisons You could probably re-factor the query to avoid some … Read more