Once your PostgreSQL database and tables are setup, you can then move to Python to perform any Data Analysis or Wrangling required. Now that you know how to setup a database, create a table and populate in PostgreSQL, you can explore the other common SQL commands as explained in the following tutorials: We can use these two commands together to a table of ‘orders’ in a database as: SELECT id, account_id, total_amt_usd FROM orders ORDER BY total_amt_usd DESC LIMIT 5 Explore other SQL commands The ORDER BY statement allows us to order our table by any row. This can be much faster for loading than if we load the entire dataset. For example, let’s say we have a table of orders with several columns but we are only interested in a subset of three: SELECT id, account_id, occurred_at FROM ordersĪlso, the LIMIT statement is useful when you want to see just the first few rows of a table. Notice the columns need to exist in this table. FROM is where you tell the query what table you are querying from. SELECT is where you tell the query what columns you want back.
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