The Impala Query Language and Built-in Functions - Learning Cloudera Impala - page 76

FROM table_name
WHERE column_name operator value
GROUP BY column_name;
In the following example, we are counting items on ID from table1 and then
grouping them by ID from table2 :
SELECT table1.Name,COUNT(table2.ID) AS
TotalOrders FROM table2
LEFT JOIN table1
ON table2.ID=table1.ID
GROUP BY Name;
• ORDER BY : The ORDER BY clause is used with SQL statements to sort the
result data by one or more columns. The sorting is done in ascending or-
der by default, and to change sort order you can use DESC at the end of the
statement. The syntax of the ORDER BY clause is shown in the following ex-
ample:
SELECT column_name,column_name
FROM table_name
ORDER BY column_name,column_name ASC|DESC;
Example:
SELECT * FROM citizens ORDER BY state;
SELECT * FROM items ORDER BY price DESC;
• HAVING : The HAVING clause is also used with aggregate functions such as
COUNT() , AVG() , SUM() , MIN() , or MAX() , when a filter operation is con-
ducted on a SELECT query. This clause also works with GROUP BY in some
cases. The syntax of a HAVING clause is as follows:
SELECT column_name,
aggregate_function(column_name) FROM
table_name
WHERE column_name operator value GROUP