Connect Excel

Connect an Excel source to load .xlsx workbooks into the Lake. You can add workbooks from this computer, or read them from a folder on an SFTP server, and you choose how their sheets become tables.

Create an Excel source

Open Lake and click Add datasource, then choose the Excel source in the picker. Supported connectors describes the picker and the shared fields.
Enter a Name of at least 3 characters and a Code of letters and numbers, at least 2 characters, and choose a Folder if you want one.
In the Configuration section, choose a Connection Type: Upload Excel (the default) or SFTP.
Add the workbooks or fill in the server fields, as described below.
Choose how the source processes the files and builds tables.
Click Add. On an existing source the button reads Save, and Duplicate creates a copy.

Once the source is saved, import its tables.

Add workbooks from this computer

Choose Upload Excel as the Connection Type.

Drop your workbooks onto Drop Excel file here, or click browse. The zone notes .xlsx files, up to 300 per save.
Check the list that appears under the zone. Each row shows the file's name, size, date and a badge: existing for a stored workbook, new for one you just added, and replace for one whose name matches a stored workbook.

Each workbook can be up to 1 GB.
One save adds at most 300 files. If you add more, the extras are not added and the form shows One save uploads at most 300 files; any beyond that were not added. Save, then add the rest.
Download file saves a stored workbook to your computer; it appears beside stored files. Download All appears when you edit an existing source and downloads all stored files as one zip (tooltip Download all files).
Remove file takes a file out of the list. Removing a stored workbook is saved with the form, so it is deleted when you save.

An Upload Excel source needs at least one file. With an empty list, the save is blocked and the form shows At least one file is required for upload connection type.

Choose how the files are processed

Processing Type sets how the files are handled: Process together (Process all files together as a single batch) or Process one by one (Process each file individually). Process together is the default.

How the sheets become tables is set with Processing Method:

Option	What it does
Each file's sheet as separate table	Create individual tables for each sheet in every file
Union sheets inside file	Combine all sheets within each file into a single table per file
Union tables by sheet names	Combine sheets with matching names across all files
Union all sheets and tables	Combine all sheets from all files into a single table

The same card holds these options for the batch:

Transpose table data: Switch rows and columns in the resulting table.
Convert time format: Convert datetime header values to time format when possible.
Skip table validation: Skip automatic table structure validation.
First row is header: Use the first row as column headers.

With Process one by one, each file row carries its own options: Union sheets, Transpose, Convert time, Skip validation and First row is header.

Read workbooks from a server

Choose SFTP as the Connection Type and fill in every field.

Setting	What it does
Host	The server name or IP address.
Port	The server port. Defaults to 22.
Username	The sign-in name.
Password	The sign-in password. After you save, it is not shown again: the field reads Stored password, with Replace.
Remote Directory	The folder that holds the workbooks. The placeholder reads Enter remote directory and the hint reads Specify the remote directory path (e.g., /folder1/folder2).

The Remote Directory must start with / and must not end with /, for example /folder1/folder2. A path that breaks the rule blocks the save with Directory must start with '/' and must not end with '/' (e.g. /folder1/folder2).
Test connection is offered for an SFTP source only; it checks that the server can be reached with these settings. An Upload Excel source has nothing to reach, so no test is shown for it.
An SFTP source chooses its Processing Method and batch options the same way as an upload.

Edit or duplicate a source

When you edit a saved source, the form fills with its settings and the stored workbooks appear with the existing badge. Download All is available here. The button reads Save.
Connection Type and Processing Type are locked on an existing source; duplicate the source to set them differently.
Duplicate creates a copy. Set the values you want on the copy, including Connection Type and Processing Type.

Limits and edge cases

Accepted files: .xlsx only. Up to 1 GB per workbook, up to 300 files per save.
An Upload Excel source needs at least one file to save.
An SFTP source needs every field, and the Remote Directory must start with / and must not end with /.
Connection Type and Processing Type are locked when you edit; duplicate the source to change them.
A workbook you have just added has no Download file action until it is stored; download actions cover stored files, and Download All appears in edit mode only.
An upload that exceeds the allowed size drops and the form shows File Too Large with The uploaded file exceeds the maximum allowed size. Please upload a smaller file.

For the messages you may see while you connect an Excel source, read Lake troubleshooting.

Questions, answered

What does the Excel drop zone accept?

.xlsx workbooks. Each workbook can be up to 1 GB.

How many workbooks can I add in one save?

Up to 300. If you add more, the extra files are not added and the form shows One save uploads at most 300 files; any beyond that were not added. Save, then add the rest.

What happens when I add a workbook that has the same name as a stored one?

It is marked replace and takes the place of the stored workbook when you save.

Why can't I download a workbook I just added?

The download actions cover stored workbooks. Download file appears beside stored files, and Download All appears when you edit an existing source. A file you have just added is not stored until you save.

Why does a large upload show File Too Large?

The upload exceeded the allowed size and the request dropped. Keep workbooks to 1 GB or less and upload again.

Can I read workbooks from a server instead of uploading them?

Yes. Choose SFTP as the Connection Type and fill in Host, Port, Username, Password and Remote Directory. Test connection is available for SFTP sources, and the Remote Directory must start with / and must not end with /.

What is the difference between Process together and Process one by one?

Process together handles all files as a single batch, and you set the processing options once for it. Process one by one processes each file on its own, and each file row gets its own options: Union sheets, Transpose, Convert time, Skip validation and First row header.

How do the sheets of my workbooks become tables?

Processing Method decides it. Each file's sheet as separate table gives every sheet its own table; the Union options combine sheets inside a file, sheets with matching names across files, or everything into one table.

What changes when I edit a saved Excel source?

The form opens filled with the saved settings, stored workbooks show the existing badge and Download All is available. Connection Type and Processing Type are locked, and the button reads Save.

Can I duplicate an Excel source?

Yes. Duplicate creates a copy. Set the values you want on the copy, including Connection Type and Processing Type.

Is this the same as Excel Workbook in Load files?

No. This page covers the Excel connection form: workbooks come from this computer or an SFTP server, and the form's processing options build the tables. Excel Workbook is a file source that uses the file form, where workbooks can also come from FTP or an S3 bucket and where format and grouping options apply; see Load files and Supported connectors.