spark-instrumented-optimizer/docs/sql-ref-syntax-qry-select-having.md

---
layout: global
title: HAVING Clause
displayTitle: HAVING Clause
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---
The <code>HAVING</code> clause is used to filter the results produced by
<code>GROUP BY</code> based on the specified condition. It is often used
in the conjunction with a [GROUP BY](sql-ref-syntax-qry-select-groupby.html)
clause.

### Syntax
{% highlight sql %}
HAVING boolean_expression
{% endhighlight %}

### Parameters
<dl>
  <dt><code><em>boolean_expression</em></code></dt>
  <dd>
    Specifies any expression that evaluates to a result type <code>boolean</code>. Two or
    more expressions may be combined together using the logical 
    operators ( <code>AND</code>, <code>OR</code> ).<br><br>

    <b>Note</b><br>
    The expressions specified in the <code>HAVING</code> clause can only refer to:
     <ol>
      <li>Constants</li>
      <li>Expressions that appear in GROUP BY</li>
      <li>Aggregate functions</li>
    </ol>
  </dd>
</dl>

### Examples
{% highlight sql %}
CREATE TABLE dealer (id INT, city STRING, car_model STRING, quantity INT);
INSERT INTO dealer  VALUES (100, 'Fremont', 'Honda Civic', 10),
                          (100, 'Fremont', 'Honda Accord', 15),
                          (100, 'Fremont', 'Honda CRV', 7),
                          (200, 'Dublin', 'Honda Civic', 20),
                          (200, 'Dublin', 'Honda Accord', 10),
                          (200, 'Dublin', 'Honda CRV', 3),
                          (300, 'San Jose', 'Honda Civic', 5),
                          (300, 'San Jose', 'Honda Accord', 8);

-- `HAVING` clause referring to column in `GROUP BY`.
SELECT city, sum(quantity) AS sum FROM dealer GROUP BY city HAVING city = 'Fremont';

  +-------+---+
  |city   |sum|
  +-------+---+
  |Fremont|32 |
  +-------+---+

-- `HAVING` clause referring to aggregate function.
SELECT city, sum(quantity) AS sum FROM dealer GROUP BY city HAVING sum(quantity) > 15;
 
  +-------+---+
  |   city|sum|
  +-------+---+
  | Dublin| 33|
  |Fremont| 32|
  +-------+---+

-- `HAVING` clause referring to aggregate function by its alias.
SELECT city, sum(quantity) AS sum FROM dealer GROUP BY city HAVING sum > 15;

  +-------+---+
  |   city|sum|
  +-------+---+
  | Dublin| 33|
  |Fremont| 32|
  +-------+---+

-- `HAVING` clause referring to a different aggregate function than what is present in
-- `SELECT` list.
SELECT city, sum(quantity) AS sum FROM dealer GROUP BY city HAVING max(quantity) > 15;

  +------+---+
  |city  |sum|
  +------+---+
  |Dublin|33 |
  +------+---+

-- `HAVING` clause referring to constant expression.
SELECT city, sum(quantity) AS sum FROM dealer GROUP BY city HAVING 1 > 0 ORDER BY city;
  
  +--------+---+
  |    city|sum|
  +--------+---+
  |  Dublin| 33|
  | Fremont| 32|
  |San Jose| 13|
  +--------+---+

-- `HAVING` clause without a `GROUP BY` clause.
SELECT sum(quantity) AS sum FROM dealer HAVING sum(quantity) > 10;
  +---+
  |sum|
  +---+
  | 78|
  +---+
 
{% endhighlight %}