From the course: Advanced SQL for Data Science: Time Series
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Evaluating query performance with EXPLAIN - SQL Tutorial
From the course: Advanced SQL for Data Science: Time Series
Evaluating query performance with EXPLAIN
- [Instructor] I'm continuing with pgAdmin but I've closed up the window that had the script re-executed. So I'm going to to navigate over to the tree and open the time_series schema, and then go down to the Tables section and click on utilization. And, I do that so that when I come up here to Tools and open a Query Tool window, it'll open that by default in that schema. Now, I'm just going to do a simple select statement so let's select star from utilization, and I'm going to specify the name of the schema first and then the table name. Now I'm going to execute this but there's no data in the table so nothing will show up here. But that's okay. What I want to do is show a couple of commands that we'll use throughout this course. One is called the Explain command. And, the Explain is added with any sequel statement or sequel query and what that does when you execute is it provides an description of how the query's executed. Now because there's no data in this table, the Explain plan…
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