---
title: Searching & Filtering | Plaza Docs
description: Find features by element type, tag filters, ID lookups, expressions, and data source in PlazaQL.
---

## Searching for features

The `search()` function is the starting point for most queries. Pass tag filters as keyword arguments:

```
// Find restaurants
search(amenity: "restaurant");


// Find supermarkets that sell organic
search(shop: "supermarket", organic: "yes");
```

### Element types

By default, `search()` returns all element types (nodes, ways, and relations). Pass a type as the first argument to filter:

```
// Nodes only (points)
search(node, amenity: "cafe");


// Ways only (lines and polygons)
search(way, building: *);


// Relations only
search(relation, type: "route");


// Explicit all (same as default)
search(nwr, amenity: "school");
```

You can also pass multiple types by listing them: `search(node, way, ...)` searches both nodes and ways.

### Dataset source

Query your own custom datasets using the `dataset()` source function:

```
// Query a single dataset by slug
search(dataset("store-locations"));


// Query multiple datasets
search(dataset("stores", "warehouses"));


// Mix custom data with OSM features
search(dataset("stores"), node, amenity: "cafe")
  .within(boundary(name: "Manhattan"));


// All standard methods work on dataset results
search(dataset("office-locations"))
  .around(500, point(40.7484, -73.9856))
  .limit(10);
```

Dataset slugs are assigned when you create a dataset via the REST API. You can query up to 20 datasets in a single `dataset()` call. See the [Datasets guide](/guides/datasets/index.md) for upload and management details.

### ID filter

Look up specific elements by OSM ID:

```
// Single ID
search(node, id: 12345);


// Multiple IDs
search(node, id: [1, 2, 3]);


// Combine with other filters
search(way, id: [100, 200, 300], highway: *);
```

### Tag filters

PlazaQL supports seven tag filter types:

```
// Exact match
search(amenity: "cafe");


// Not equals
search(amenity: !"fast_food");


// Regex match
search(name: ~"^Star");


// Case-insensitive regex
search(name: ~i"starbucks");


// Negated regex
search(name: !~"McDonald");


// Key exists (any value)
search(amenity: *, wheelchair: *);


// Key does not exist
search(amenity: "cafe", drive_through: !*);
```

Multiple filters in the same `search()` are combined with AND — all must match.

### Key and value regex

Both the key and value in a tag filter can be regex patterns. This is useful for matching tag families or numeric values across multiple keys:

```
// All address tags that start with a number
search(node, ~"^addr:": ~"^[0-9]");


// Any name tag (name, name:en, name:de, etc.) with any value
search(node, ~"^name:": *);


// Find elements with any addr: tag
search(~"^addr:": *);
```

Key regex uses the `~"pattern"` syntax on the left side of the colon. Combine it with value patterns (exact, regex, exists) on the right.

## Tag filtering with `.filter()`

The `.filter()` method applies tag filters after search or set operations. It uses the same syntax as `search()` tag filters:

```
// Filter a union — find all food places, keep only wheelchair-accessible
$food = search(amenity: "restaurant") + search(amenity: "cafe");
$food.filter(wheelchair: "yes");
```

This is especially useful after combining sets, where you want to filter the combined result:

```
$mc = search(name: "McDonald's");
$sb = search(name: "Starbucks");
$bk = search(name: "Burger King");


($mc + $sb + $bk)
  .within(geometry: $berlin)
  .filter(wheelchair: "yes", diet__vegan: *)
  .limit(count: 50);
```

Multiple `.filter()` calls combine with AND:

```
search(amenity: "restaurant")
  .filter(cuisine: ~"italian")
  .filter(outdoor_seating: "yes");
```

### Expression filters

For filtering based on computed values — tag arithmetic, string operations, or geometry properties — use `.filter()` with an expression instead of tag syntax:

```
// Capacity greater than 50
search(amenity: "theatre")
  .within(geometry: $berlin)
  .filter(number(t["capacity"]) > 50);


// Roads longer than 1km
search(way, highway: "primary")
  .within(geometry: $city)
  .filter(length() > 1000);


// Buildings with area over 500 sq meters
search(way, building: *)
  .bbox(40.7, -74.0, 40.8, -73.9)
  .filter(area() > 500);
```

Expression filters use the full [expression language](/guides/plazaql/advanced#expressions/index.md) — tag access with `t["key"]`, arithmetic operators, geometry functions, and comparisons. See the [Expressions](/guides/plazaql/advanced#expressions/index.md) section for the complete reference.