Merge
Home → Merge Queries joins two queries on one or more columns. The join kinds are the SQL ones plus two extras:
| Kind | Keeps |
|---|---|
| Left outer | All from first, matches from second |
| Right outer | All from second, matches from first |
| Full outer | Everything from both |
| Inner | Matches only |
| Left anti | Only first-table rows with no match |
| Right anti | Only second-table rows with no match |
The anti joins are the useful additions — they answer which of these have no match directly, which is a query rather than a menu option in SQL.
Check the match rate
After merging, the new column shows Table for matched rows and null for unmatched. Filtering to nulls tells you immediately how many failed to match.
Trailing whitespace and case differences are the usual cause of a merge matching nothing on values that look identical. Apply Format → Trim and Lowercase to both key columns before merging.
Expanding
The merged column holds nested tables. Click the expand icon and choose which columns to bring through — take only what you need, since every extra column is loaded and stored.
Untick use original column name as prefix unless you want Products.ProductName.
Append
Append Queries stacks rows — twelve monthly files into one table. Columns are matched by name; anything present in one query and not another comes through as null.
For a folder of files, Get Data → Folder is better than appending manually: it reads every file matching the criteria, including ones added later.
Merge or model
You do not have to merge. Where two tables have a genuine relationship, loading both and creating a model relationship is usually better — it keeps the star schema, allows filtering in both directions, and avoids widening a fact table.
Merge when you need a lookup value denormalised onto a row for a calculated column, or when the result is genuinely one table.