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Turning ON this button during normal query execution will return the query data result set as well as the visual explain execution plan with a diagram. The execution plan contains the actual cost for running the query.
Execute Explain Button
The information returned for this query execution will be a text version of the explain plan and not the visual explain plan grid with a diagram. In this case, no data is returned because the query is never executed. The plan describes the access path that will get used when the query is executed. It only shows the plan that Redshift will execute if the query is run under current operating conditions. If you change the schema or data for a table and run the analyze command again to update the statistical metadata, the query plan might be different. 
In DBA Tools Instance Manager
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- Type = Query – Lets you scroll through queries that were executed based on your filter selection.
- Type = All - Let's you scroll through a list that contains queries, DDL, and utility statements. This works similarly to the query list described above. However, this list also contains DDL and utility statements and there is no execution plan for them. You will notice that when you select one of these the “Execution Plan” tab disappears. The execution plan tab is only available for queries.
In the case where visual explain is executed, an explain plan grid with detailed summarized information about each step in the query process will be displayed. This plan grid should be read from the bottom up. When you right-click on this grid, a pop-up menu will show you some other options that are available such as an explanatory diagram. Clicking the “Explain Diagram” shows a block hierarchical diagram of the steps for executing this query.
- Type = Utility or DDL – This does not apply since there are no queries in these lists.
