How to deduplicate in presto?

@lew 

In Presto, you can deduplicate data by using the DISTINCT keyword in your query. Here is an example of how to deduplicate data in Presto:

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SELECT DISTINCT column1, column2, column3
FROM table_name;

This query will return only unique combinations of values in columns column1, column2, and column3 from the specified table.

You can also use the GROUP BY clause along with the MAX, MIN, or COUNT aggregate functions to deduplicate data. Here is an example:

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SELECT column1, MAX(column2), COUNT(column3)
FROM table_name
GROUP BY column1;

This query will return one row for each unique value in column1, with the maximum value of column2 and the count of column3. This effectively deduplicates the data based on the values in column1.