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

# SQL Interface

> How to query semantics in SQL via JDBC

## Intro

It is possible to query Honeydew semantic model via a BI tool or a SQL editor.

Anything that support JDBC can connect to Honeydew.

A sample query looks like:

```sql theme={null}
SELECT
    "orders.o_orderdate",
    AGG("lineitem.revenue")
FROM world.world
WHERE "customer.c_mktsegment" = 'MACHINERY'
HAVING AGG("orders.count") < 10
GROUP BY 1
ORDER BY 1 DESC
LIMIT 30
```

This would the last month daily revenue of machinery customers.

### The world as one big flat table

The `world` is a virtual table that includes as columns every attribute of every entity that is exposed to the SQL interface.

Building the correct JOIN logic happens behind the scenes when `world` is queried.

<Tip>
  `world` is the whole semantic model. If want to use the SQL interace on a subset of the world, for performance or access control reasons,
  can instead use the SQL interface on a [domain](/domains#domains-on-sql-interface).
</Tip>

### Domains in SQL interface

[Domains](/domains) in the JDBC interface present in a similar way to `world`: every domain is a flat table.

All the domains are in the `domains` schema:

```sql theme={null}
SELECT
    "orders.o_orderdate",
    AGG("lineitem.revenue")
FROM domains.my_domain
GROUP BY 1
```

### Parameters in the SQL interface

It is possible to set values for parameters through the SQL interface. See [parameters](/parameters) for more info.

### Branches in the SQL interface

When connecting to the SQL interface, add `__branch_name` to the catalog name to connect to a development branch with the name `branch_name`.

For example, when the workspace is called `tpch_demo` and has a production branch and a development branch called `dev`,
the corresponding JDBC catalogs would be called `tpch_demo` and `tpch_demo__dev`.

## Interface

### Attributes

Attributes are exposed as columns in the virtual table.

Any expression can be used on attributes, including aggregations (like a `SUM` or a `COUNT`) can be used.

### Metrics

Metrics are exposed as columns in the virtual table.

When using an aggregation function (like `SUM`) on a metric column the function is ignored,
and the actual metric computation runs instead.

`AGG` is special function that when run on a metric, directly invokes its computation.

<Tip>
  For clarity of SQL, prefer using the `AGG` function to get metric value, as in the example above.
</Tip>

### Filtering and Computation Order

When using SQL interface, the filters provided by the SQL query (with `WHERE` and with `HAVING`) are applied.

For more details, see [order of computation](/advanced-modeling/order-of-computation)

<Tip>
  You can filter on attributes using `WHERE` and on metrics using `HAVING`
</Tip>