Generally, fields with the same name within the same buying door can be joined
together across tables. For example, adh.google_ads_impressions.impression_id
can be joined with adh.google_ads_clicks.impression_id. In this example,
Google Display Ads is the common buying door, impression_id is the common field,
and google_ads_impressions and google_ads_clicks are the two different
tables.
Complexities exist that can make it difficult to join data across buying doors. Different Google products use different user IDs, and user IDs can also vary within a single product based on sign-in state.
Use the following table as a guideline for joining across products. Joins within each buying door will generally work, whereas joins between buying doors generally won't.
| Buying Door | Products | Tables | Joinable IDs |
|---|---|---|---|
| Google Display Ads | Google Video Partners (excl. YouTube) | adh.google_ads_*
|
|
| Google Marketing Platform | via Data
Transfer:
Display & Video 360 Campaign Manager 360 |
adh.dv360_dt_* adh.cm_dt_*
|
|
| YouTube Google sold | YouTube
Reserve YouTube (in Google Ads) YouTube (in Display & Video 360) |
adh.yt_reserve_*
adh.google_ads_*
adh.dv360_youtube_*
|
|
| YouTube Partner sold | Google Ad
Manager Freewheel |
adh.partner_sold_cross_sell_*
adh.freewheel_* |
|
| Key | user_id |
external_cookie |
device_id_md5 |
Examples
In addition to user and device IDs, you can join tables using a number of other fields. To learn how to join tables in Ads Data Hub, select a joinable field from the dropdown menu. This section contains a non-exhaustive set of examples.
This example demonstrates how to use user_id to join
impressions, creatives, and conversions tables.
Use case: Understand if branding campaigns drive incremental conversions.
WITH imp AS (
SELECT
user_id,
COUNTIF(campaign_id IN UNNEST(@brand_campaign_ids)) AS brand_impression,
COUNTIF(campaign_id IN UNNEST(@perf_campaign_ids)) AS perf_impression,
FROM adh.google_ads_impressions
WHERE
campaign_id IN UNNEST(ARRAY_CONCAT(@perf_campaign_ids, @brand_campaign_ids))
AND user_id != '0'
GROUP BY 1
),
conv AS (
SELECT
c.user_id,
COUNT(1) AS conv_count
FROM adh.google_ads_conversions
WHERE
impression_data.campaign_id IN UNNEST(@perf_campaign_ids)
AND conversion_type IN UNNEST(@conversion_type_list)
AND user_id != '0'
GROUP BY 1
)
SELECT
SUM(IF(has_brand_traffic AND NOT has_perf_traffic, conv_count, 0)) AS brand_only,
SUM(IF(NOT has_brand_traffic AND has_perf_traffic, conv_count, 0)) AS perf_only,
SUM(IF(has_brand_traffic AND has_perf_traffic, conv_count, 0)) AS overlap
FROM
(
SELECT
imp.user_id,
imp.brand_impression > 0 AS has_brand_traffic,
imp.perf_impression > 0 AS has_perf_traffic,
conv.conv_count
FROM imp
JOIN conv
USING (user_id)
)
This example demonstrates how to use impression_id to
link conversions data to impressions data.
Use case: Slice impression and conversion stats based on country and CTC/EVC.
SELECT
imp.location.country,
COUNT(1) AS num_imps,
SUM(IF(attribution_event_type = 'CLICK', 1, 0)) AS ctc_convs,
SUM(IF(attribution_event_type = 'ENGAGED_VIEW', 1, 0)) AS evc_convs
FROM adh.google_ads_impressions AS imp
LEFT JOIN adh.google_ads_conversions AS conv
ON (
imp.impression_id = conv.impression_id
AND conv.conversion_type IN UNNEST(@conversion_type_list))
WHERE imp.campaign_id IN UNNEST(@campaign_ids)
GROUP BY 1
This example demonstrates how to join several tables on multiple IDs.
Use case: List assets linked to a particular campaign.
SELECT
cmp.campaign_id,
adg.adgroup_id,
cr.video_message.youtube_video_id
FROM adh.google_ads_campaign AS cmp
JOIN adh.google_ads_adgroup AS adg
USING (campaign_id)
JOIN adh.google_ads_adgroupcreative AS agc
USING (adgroup_id)
JOIN adh.google_ads_creative AS cr
ON (agc.customer_id = cr.customer_id
AND agc.creative_id = cr.creative_id)
WHERE campaign_id = 123
GROUP BY 1, 2, 3
This example demonstrates how to join metadata tables.
Use case: Join an impressions table with the state metadata table to show unique cookie count and average frequency by state.
SELECT
IFNULL(reg.region_name, 'unspecified') AS state,
COUNT(DISTINCT user_id) AS users,
COUNT(1) AS impressions,
FORMAT('%0.2f', COUNT(1) / COUNT(DISTINCT user_id)) AS avg_imp_per_user
FROM adh.google_ads_impressions AS imp
LEFT JOIN adh.region AS reg
ON (imp.location.geo_region_id = reg.region_id)
WHERE
imp.location.country = 'US'
GROUP BY 1