This section refers to the

`type`

parameter that is part of a measure

`type`

can also be used as part of a`dimension`

or`filter`

, described here

`type`

can also be used as part of a dimension_group, described here

# Usage

measure: field_name {

type: measure_field_type

}

}

## Hierarchy`type` |
## Possible Field TypesMeasure## AcceptsA measure type |

This page includes additional details about the various types that can be assigned to a measure. A measure can only have one type, and defaults to `string`

if no type is specified.

Some measure types have supporting parameters, which are described within the appropriate section.

## Type Definitions

Type | Description |
---|---|

`string` |
For measures that contain letters or special characters (as with MySQL’s `GROUP_CONCAT` function) |

`date` |
For measures that contain dates |

`int` |
AVOID AS OF3.38 Replaced by `type: number` |

`number` |
For measures that contain numbers |

`count` |
Generates a count of rows |

`count_distinct` |
Generates a count of unique values within a column |

`sum` |
Generates a sum of values within a column |

`sum_distinct` |
Properly generates a sum of values when using de-normalized dataRead full documentation for complete description |

`avg` |
OLD LOOKML Generates an average of values within a column |

`average` |
Generates an average of values within a column |

`avg_distinct` |
OLD LOOKML Properly generates an average of values when using de-normalized data. Read full documentation for complete description. |

`average_distinct` |
Properly generates an average of values when using de-normalized data. Read full documentation for complete description. |

`min` |
Generates the minimum value within a column |

`max` |
Generates the maximum value within a column |

`list` |
Generates a list of the unique values within a column |

`percent_of_previous` |
Generates the percent difference between displayed rows |

`percent_of_total` |
Generates the percent of total for each displayed row |

`running_total` |
Generates the running total for each displayed row |

## string

`type: string`

is used with fields that contain letters or special characters.

The `sql`

parameter for `type: string`

measures can take any valid SQL expression that results in a string. In practice, this type is rarely used, because most SQL aggregate functions do not return strings. One common exception is MySQL’s `GROUP_CONCAT`

function, although Looker provides `type: list`

for that use case.

For example, the following LookML creates a field **Category List** by combining the unique values of a field called **Category**:

In this example `type: string`

could be omitted, because `string`

is the default value for `type`

.

## date

`type: date`

is used with fields that contain dates.

The `sql`

parameter for `type: date`

measures can take any valid SQL expression that results in a date. In practice, this type is rarely used, because most SQL aggregate functions do not return dates. One common exception is a `MIN`

or `MAX`

of a date dimension.

For example, the following LookML creates a field **Most Recent Order Date** by taking the maximum value from the **Order Date** field:

In this example `type: date`

could be omitted, and the value would be treated as a string, because `string`

is the default value for `type`

. However, you will get better filtering capability for users if you use `type: date`

. The `convert_tz`

parameter prevents double timezone conversion. This concept is described in more detail in this Discourse post.

## int AVOID AS OF3.38

As of version 3.38, use `type: number`

instead.

`type: int`

is used with numbers that you want to display with no commas or decimal places. The underlying data does *not* necessarily have to be an integer; it can also be a floating point number.

The `sql`

parameter for `type: int`

measures can take any valid SQL expression that results in a number or integer.

For example, the following LookML creates a field **Change In Inventory** by subtracting a field called **Number Of Items Returned** from **Number Of Items Sold**:

**Note:** A measure can only perform arithmetic on other measures, not dimensions. Also, the `filters`

parameter cannot be used with `type: int`

measures (see the `filters`

documentation for a workaround).

## number

`type: number`

is used with numbers or integers.

The `sql`

parameter for `type: number`

measures can take any valid SQL expression that results in a number or integer.

`type: number`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a field called **Total Profit** based on the **Total Revenue** and **Total Cost** measures, then displays it in a money format ($1,234.56):

There are several important things to keep in mind when using `type: number`

measures:

- A measure can only perform arithmetic on other measures, not other dimensions
- The
`filters`

parameter cannot be used with`type: number`

measures, but the`filters`

documentation explains a workaround `type: number`

measures will not provide suggestions to users

## count

`type: count`

performs a table count, similar to SQL’s `COUNT`

function. However, unlike writing raw SQL, Looker will properly calculate counts even if your query’s joins contain fanouts.

You do not need to include a `sql`

parameter for `type: count`

measures.

For example, the following LookML creates a field **Number Of Products**:

It is very common to provide a `drill_fields`

parameter when defining a `type: count`

measure, so that users can see the individual records that make up a count when they click on it.

## count_distinct

`type: count_distinct`

calculates the number of distinct values in a given field. It makes use of SQL’s `COUNT DISTINCT`

function.

The `sql`

parameter for `type: count_distinct`

measures can take any valid SQL expression that results in a table column, LookML dimension, or combination of LookML dimensions.

For example, the following LookML creates a field **Number Of Unique Customers** which counts the number of unique customer IDs:

## sum

`type: sum`

adds up the values in a given field. It is similar to SQL’s `SUM`

function. However, unlike writing raw SQL, Looker will properly calculate sums even if your query’s joins contain fanouts.

The `sql`

parameter for `type: sum`

measures can take any valid SQL expression that results in a numeric table column, LookML dimension, or combination of LookML dimensions.

`type: sum`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a field called **Total Revenue** by adding up the **Sales Price** dimension, then displays it in a money format ($1,234.56):

## sum_distinct

`type: sum_distinct`

is for use with de-normalized data sets. It adds up the non-repeated values in a given field, based on the unique values defined by the `sql_distinct_key`

parameter.

The usage is:

measure: field_name {

type: sum_distinct

sql_distinct_key: ${my_field_name} ;;

}

}

This is an advanced concept which may be more clearly explained with an example. Consider a de-normalized table like this:

Order Item ID | Order ID | Order Shipping |
---|---|---|

1 | 1 | 10.00 |

2 | 1 | 10.00 |

3 | 2 | 20.00 |

4 | 2 | 20.00 |

5 | 2 | 20.00 |

In this situation you can see that there are multiple rows for each order. Consequently, if you added a simple `type: sum`

measure for the **Order Shipping** column, you would get a total of 80.00, even though the total shipping collected is actually 30.00.

To get an accurate result, you can explain to Looker how it should identify each unique entity (in this case, each unique order) by using the `sql_distinct_key`

parameter. This *will* calculate the correct 30.00 amount:

Please note that every unique value of `sql_distinct_key`

must have just one, corresponding value in `sql`

. In other words, the above example works because *every* row with an **Order ID** of 1 has the same **Order Shipping** of 10.00, *every* row with an **Order ID** of 2 has the same **Order Shipping** of 20.00, and so on.

`type: sum_distinct`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

## average

`type: average`

averages the values in a given field. It is similar to SQL’s `AVG`

function. However, unlike writing raw SQL, Looker will properly calculate averages even if your query’s joins contain fanouts.

The `sql`

parameter for `type: average`

measures can take any valid SQL expression that results in a numeric table column, LookML dimension, or combination of LookML dimensions.

`type: average`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a field called **Avg Order** by averaging the **Sales Price** dimension, then displays it in a money format ($1,234.56):

## average_distinct

`type: average_distinct`

is for use with de-normalized data sets. It averages the non-repeated values in a given field, based on the unique values defined by the `sql_distinct_key`

parameter.

This is an advanced concept which may be more clearly explained with an example. Consider a de-normalized table like this:

Order Item ID | Order ID | Order Shipping |
---|---|---|

1 | 1 | 10.00 |

2 | 1 | 10.00 |

3 | 2 | 20.00 |

4 | 2 | 20.00 |

5 | 2 | 20.00 |

In this situation you can see that there are multiple rows for each order. Consequently, if you added a simple `type: average`

measure for the **Order Shipping** column, you would get a value of 16.00, even though the actual average is 15.00.

To get an accurate result, you can explain to Looker how it should identify each unique entity (in this case, each unique order) by using the `sql_distinct_key`

parameter. This *will* calculate the correct 15.00 amount:

Please note that every unique value of `sql_distinct_key`

must have just one, corresponding value in `sql`

. In other words, the above example works because *every* row with an **Order ID** of 1 has the same **Order Shipping** of 10.00, *every* row with an **Order ID** of 2 has the same **Order Shipping** of 20.00, and so on.

`type: average_distinct`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

## min

`type: min`

finds the smallest value in a given field. It makes use of SQL’s `MIN`

function.

The `sql`

parameter for `type: min`

measures can take any valid SQL expression that results in a numeric table column, LookML dimension, or combination of LookML dimensions. It will **not** work with dates; instead, see the example in `type: date`

above.

`type: min`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a field called **Smallest Order** by looking at the **Sales Price** dimension, then displays it in a money format ($1,234.56):

You cannot currently use `type: min`

measures for strings or dates, but you can manually add the `MIN`

function to create such a field, like this:

## max

`type: max`

finds the largest value in a given field. It makes use of SQL’s `MAX`

function.

The `sql`

parameter for `type: max`

measures can take any valid SQL expression that results in a numeric table column, LookML dimension, or combination of LookML dimensions. It will **not** work with dates; instead, see the example in `type: date`

above.

`type: max`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a field called **Largest Order** by looking at the **Sales Price** dimension, then displays it in a money format ($1,234.56):

You cannot currently use `type: max`

measures for strings or dates, but you can manually add the `MAX`

function to create such a field, like this:

## list

`type: list`

only works with MySQL and PostgreSQL

`type: list`

creates a list of the distinct values in a given field. It is similar to MySQL’s `GROUP_CONCAT`

function.

You do not need to include a `sql`

parameter for `type: list`

measures. Instead, you’ll use the `list_field`

parameter to specify the dimension from which you want to create lists.

The usage is:

measure: field_name {

type: list

list_field: my_field_name

}

}

For example, the following LookML creates a measure **Name List** based on the **Name** dimension:

Please note that `type: list`

measures cannot be filtered on.

## percent_of_previous

`type: percent_of_previous`

calculates the percent difference between a cell and the previous cell in its column.

The `sql`

parameter for `type: percent_of_previous`

measures must reference another, numeric measure.

`type: percent_of_previous`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a measure **Count Growth** based on the **Count** measure:

In the Looker UI, this would look like:

Note that `percent_of_previous`

values depend on sort order. If you change the sort, you must re-run the query to re-calculate the `percent_of_previous`

values. In cases where a query is pivoted, `percent_of_previous`

runs across the row instead of down the column. You cannot currently change this behavior.

Additionally, `percent_of_previous`

measures are calculated *after* data is returned from your database. This means that you should not reference a `percent_of_previous`

measure within another measure; since they might be calculated at different times, you may not get accurate results. It also means that `percent_of_previous`

measures cannot be filtered on.

## percent_of_total

`type: percent_of_total`

calculates a cell’s portion of the column total. Note that the percentage is being calculated against the total of the *displayed* rows, and *not* the total of all possible rows.

The `sql`

parameter for `type: percent_of_total`

measures must reference another, numeric measure.

`type: percent_of_total`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a measure **Percent Of Total Gross Margin** based on the **Total Gross Margin** measure:

In the Looker UI, this would look like:

In cases where a query is pivoted, `percent_of_total`

runs across the row instead of down the column. If this is not desired, add `direction: column`

to the measure definition.

Additionally, `percent_of_total`

measures are calculated *after* data is returned from your database. This means that you should not reference a `percent_of_total`

measure within another measure; since they might be calculated at different times, you may not get accurate results. It also means that `percent_of_total`

measures cannot be filtered on.

## running_total

`type: running_total`

calculates a cumulative sum of the cells along a column. It cannot be used to calculate sums along a row, unless the row has resulted from a pivot.

The `sql`

parameter for `type: running_total`

measures must reference another, numeric measure.

`type: running_total`

fields can be formatted by using the `value_format`

or `value_format_name`

parameters.

For example, the following LookML creates a measure **Cumulative Total Revenue** based on the **Total Sale Price** measure:

In the Looker UI, this would look like:

Note that `running_total`

values depend on sort order. If you change the sort, you must re-run the query to re-calculate the `running_total`

values. In cases where a query is pivoted, `running_total`

runs across the row instead of down the column. If this is not desired, add `direction: column`

to the measure definition.

Additionally, `running_total`

measures are calculated *after* data is returned from your database. This means that you should not reference a `running_total`

measure within another measure; since they might be calculated at different times, you may not get accurate results. It also means that `running_total`

measures cannot be filtered on.