![]() ![]() ![]() the least common names: SELECT * FROM baby_names ORDER BY state DESC, count ASC The following (somewhat nonsensical) query will return the rows in reverse-alphabetical order of state, then in ascending order of count, i.e. The ORDER BY keywords are only used once. ![]() Just add more column names and ordering keywords – i.e. a tie, we can specify more columns to use in the sorting criteria. In the case when the column to sort by has duplicate values, i.e. To sort the baby names table in descending order of count: SELECT * FROM baby_names ORDER BY count DESC If we want to explicitly specify ascending order, we use the ASC keyword: ORDER BY "some_column_name" ASC The syntax looks like this: ORDER BY "some_column_name" DESC If we want to find the rows with the largest count values, we use the DESC keyword. When it comes to numbers, that means smallest first. Here's a standalone example: SELECT * FROM baby_names ORDER BY count īy default, ORDER BY sorts in ascending order. The basic syntax is: ORDER BY "some_column_name" The ORDER BY clause, as you can imagine, let's us specify the sorting order of the returned data rows. Thus, the following queries will not work: SELECT * LIMIT 1 FROM baby_names SELECT * LIMIT 1 FROM baby_names The ORDER BY clause So the key thing to notice is the specific order and arrangement of the SQL statement: just as FROM comes after the SELECT clause, LIMIT comes after both. Mind the ordering of the syntaxĪt this point, we've only covered three different clauses. Even before you get to exporting data, returning 1,000,000 rows will just be slower than returning 10 rows, all other things being equal. LIMIT is a good way to reduce the execution time. But the main concern is that in the real-world, retrieving data rows takes computational time. Why use LIMIT when, well, we could just have all the data? Remember that more data is not always better. Pretty easy, there's not much more to LIMIT than the keyword itself, followed by the number of rows we want to see. With LIMIT, we can restrict the number of rows returned: SELECT * FROM baby_names LIMIT 1 With SELECT, we were able to specify exactly how many columns we wanted in the returned dataset. ![]()
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