> ## Documentation Index
> Fetch the complete documentation index at: https://arize-ax.mintlify.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Arize Query Language Syntax

> Breakdown of the Arize Query Language

### Custom Metric Syntax Overview

Custom metrics use an Arize SQL-like query language.

```csharp theme={null}
SELECT
< AGG_FUNC | METRIC_FUNC >(exprs) 
[FILTER (WHERE exprs)]  
[CASE WHEN ...END ]
[ <OPERATOR> { < AGG_FUNC | ARIZE_METRIC >(exprs) | constant }]  … 
FROM model
[WHERE (exprs) ]
```

#### `SELECT`

Every query starts with a `SELECT` statement.

#### `FROM`

The `FROM` statement should be`FROM model`, where `model` refers to the model that the custom metric was created under.

#### Constants

A constant can be a number or string. Strings use single quotes like this: `'this is a string'`. Numbers can be floats or integers.

#### Expressions

```html theme={null}
dimension
constant
[ dimension | constant | (exprs) ] <OPERATOR> [ dimension | constant | (exprs) ]
```

An expression is a statement composed of simple math or boolean operators. An expression does not have an aggregation function within it. Expressions can include nested expressions, for example, A \* (B + C). Expressions return the same number of rows as those that go into it.

#### Dimensions

A dimension is any feature, tag, prediction, actual, or span property of a model. A dimension can either be of type string or of type numeric.

| Type          | Invocation                                                               | Description                                                                                                                                                  |
| ------------- | ------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Feature       | `feature_name` or `"feature name"`                                       | Features can be referenced directly or use double quotes.Note: if there are spaces in your feature name, you must use double quotes.                         |
| Tag           | `tag_name` or `"tag name"`                                               | Tags can be referenced directly or use double quotes.Note: if there are spaces in your tag name, you must use double quotes.                                 |
| Prediction    | `categoricalPredictionLabel scorePredictionLabel numericPredictionLabel` | For scored categorical models, there is `categoricalPredictionLabel` and `scorePredictionLabel `For numeric models, there is only `numericPredictionLabel`   |
| Actual        | `categoricalActualLabel scoreActualLabel numericActualLabel`             | For scored categorical models, there is `categoricalActualLabel` and `scoreActualLabel`For numeric models, there is only `numericActualLabel`                |
| Span Property | `span_property` or `"span property"` or `"span. property"`               | Span properties can be referenced directly or use double quotes.Note: if there are spaces or periods in your span property name, you must use double quotes. |

#### Comments

Comments can be added to your query in one of two ways:

Single line comment (shortcut is `CMD + /`)

```python theme={null}
-- This is a single line comment
```

Multi-line comments

```javascript theme={null}
/* This
 * is a 
 * multiline comment
 */
```