====ARDI Query Language====

Although there are a variety of API functions available, most queries you'll make to ARDI use the ARDI Query Language (AQL).

Although the name is similar, AQL is **not** based on the SQL language that you might be familiar with from traditional relational databases.

This is because SQL struggles when it comes to complex relationships - it's hard to make an SQL query that deals with a large number of parent-to-child connections.

===Endpoint===

AQL is REST-based, so you can send an AQL query from virtually any modern language and platform.

There are three main URLs you might want to use to access query language...

**To Write A Query Interactively**

    <ardiserver>/aql/api/

**For Normal Queries:**

    <ardiserver>/aql/api/query?query=<query>

**For Tabulated Data:**

    <ardiserver>/aql/api/table?query=<query>&format=<format>

For example, you can see the current values from **Wind Turbine #1** from the following URL...

[[https://demo.optrix.com.au/s/ex/aql/api/query?query=%27Wind+Turbine+%231%27+ASSET+ALLPOINTS]]

===Normal vs Tabulated Queries===

Normal AQL queries return each point of data independently, based on how they are stored in their back-end system.

However when you're dealing with **history**, the different timings can be a significant issue when you are trying to create graphs, analytics and particularly machine-learning solutions.

The **tabulated** endpoint is used when requesting history from AQL - we'll cover its use in the next pages.

===Normal Query Result===

Normal (ie. non-tabulated) query results are returned as a JSON-encoded object.

<code json>
{
  "query": "'Wind Turbine #1' ASSET ALLPOINTS",
  "results": [
    {
      "type": "pointlist",
      "value": [
        {
          "assetid": 42,
          "sourceid": 42,
          "value": "WT-1",
          "rawvalue": "WT-1",
          "propid": 2,
          "fullvalue": "WT-1",
          "type": "TAG",
          "name": "Wind Turbine #1",
          "propname": "Equipment Tag",
          "ern": "WT-1"
        },
        {
          "assetid": 42,
          "sourceid": 42,
          "value": "663.30206458",
          "rawvalue": "663.30206458",
          "propid": 28,
          "fullvalue": "663.30206458| V|0|700|1|^ V",
          "type": "MEASUREMENT",
          "name": "Wind Turbine #1",
          "code": "42:28:measurement",
          "units": " V",
          "min": "0",
          "max": "700",
          "places": "1",
          "propname": "Voltage",
          "ern": "WT-1"
        },
        {
          "assetid": 42,
          "sourceid": 42,
          "value": "85.54490912",
          "rawvalue": "85.54490912",
          "propid": 31,
          "fullvalue": "85.54490912|%|0|100|1|^%",
          "type": "MEASUREMENT",
          "name": "Wind Turbine #1",
          "code": "42:31:measurement",
          "units": "%",
          "min": "0",
          "max": "100",
          "places": "1",
          "propname": "Load",
          "colours": {
            "0": "0000ff",
            "35": "247b00",
            "68": "0eff00",
            "91": "faff00",
            "100": "ff0000"
          },
          "ern": "WT-1"
        }]
  }]
}
</code>

Certain AQL queries may return //multiple sets// of results (for example, sets of values at different time ranges, or distinct min, max and average-value queries). This is why the response includes an array of objects in the //Response// section.

Each result has a //type//. In the example above, it's a [[pointlist|POINTLIST]].  Pointlists are a list of [[points|points]] (property values). Each value includes...

^Name^Meaning^
|type|The type of the property (ie. TEXT, MEASUREMENT, STATUS, ENUM)|
|name|The name of the asset the property belongs to|
|propname|The name of the property|
|assetid|The numeric ID associated with the ARDI asset|
|propertyid|The numeric ID associated with the ARDI property|
|value|The current value of the property, delimited with vertical bars|

 There are also some //optional// attributes depending on the type of property...

^Name^Meaning^Type^
|min/max|The minimum and maximum [[expected value]]|MEASUREMENT|
|units|The units of measurement|MEASUREMENT|
|map|A lookup table from numeric value to text|LOOKUP/ENUM/STATUS|
|colours|A table of colour values for analogue values|MEASUREMENT|
|colourmap|A table of colour values for discrete values|ENUM/STATUS|
|icons|A table of PNG images for discrete values|ENUM/STATUS|
|history|A list of time/value pairs giving the value over time|[[bound|BOUND]] ONLY|

===Continue Reading===

[[AQL Tabular Data]]