---
title: table.lookup_bool
summary: null
url: >-
  https://www.fastly.com/documentation/reference/vcl/functions/table/table-lookup-bool
---

```
BOOL table.lookup_bool(ID id, STRING key, BOOL default)
```

**Available in:** all subroutines

Looks up the key `key` in the table `id`. When the key is present, its
associated value will be returned. When the key is absent, the `default`
value is returned. The `default` value is required.

## Example

```vcl
table highres BOOL {
  "broadband": true,
  "cable": true,
  "dialup": false,
  "mobile": false, # fast but expensive
  "oc12": true,
  "oc3": true,
  "t1": false, # T1 is 1.544Mbps
  "t3": true,
  "satellite": true,
  "wireless": true,
  "xdsl": true
}

# The idea here is to decide to deliver high-resolution media by default
# when we have a sure idea that the client's connection is suitable, and
# to give lower-resolution content when we're sure it's not suitable
# (perhaps also offering a link to a high-res version in that case).
#
# See client.geo.conn_speed

declare local var.highres BOOL;
declare local var.fallback BOOL;

set var.fallback = false; # Could populate this based on some other information
set var.highres = table.lookup_bool(highres, client.geo.conn_speed, var.fallback);
```