Table preview, filters and export

The Preview tab of a table popup shows a table's rows so you can check the data without writing a query. You can search, filter, sort, page through and download the rows. For deploying, running and deleting tables, see Deploy, run, truncate and monitor tables.

Read a preview

1. Open the table and go to Preview.
2. Use the toolbar: the search box, Toggle column visibility, the export control and Refresh data to load the newest rows again.

The grid is a dense, read-only view. It loads one page at a time from the platform: paging, filtering and sorting run on the server, so a large table is never loaded whole.

Search, filter and sort

1. Type in the search box. The preview keeps the rows where any text column contains the text you type, ignoring case.
2. Open a column's filter menu and tick the values you want. A column carries one filter at a time.
3. Sort a column ascending or descending.

The control itself works the same way as on other grids; value lists, condition filters, clearing filters and the sort cycle are described in Filter, sort and search.

• Filter menus cascade: each menu offers the values that exist under the other columns' active filters and your search, and changing any of them reloads the lists. Values you already ticked stay listed.
• Date filter menus are a plain sorted list.
• To find rows where a column has no value, choose the empty entry in its menu.
• If a menu cannot load its values, DataMind shows Failed to load filter options (or the server's reason when one is given). Open the menu again, or change another filter, to reload the lists.

Move between pages

• Pick a page size of 20, 50, 100 or 500 rows. The default is 20.
• The preview returns to the first page whenever the search, a filter or the sort changes.
• A preview request is capped at 1,000 rows.
• Where a preview shows query statistics, they are the query's elapsed time, the rows read and the bytes read.

Download the rows

The export control works like it does on other grids: pick the format, then click the download button. See Export and copy for the control itself.

• A preview offers Excel, CSV, JSON and TSV.
• The download is built from the same search, filters and sort as the grid.
• The file is named after the popup. When the popup has no name of its own, it falls back to the table's id, such as table_123.
• In Excel downloads, a column that holds a list is rewritten from its raw form to plain text, in the form a, b, c.
• When a download fails, DataMind shows the server's reason, or Export failed when there is none.

In a source preview

A Lake table's Preview tab has two sides. Lake shows the table's own rows, and Source shows the rows as they come from the source system. Switch between them from the toolbar.

• The Source side loads only when DataMind can resolve the table's source: its datasource, database and schema. When it cannot, the grid stays empty.
• Its columns come from the first row of the data.
• A download from the Source side adds _Source to the file name, so it stays distinct from the Lake download.

For the table setup around the preview, see Configure a table.

Questions, answered

Which columns does the search check?

Every text column, ignoring case, and the match can appear anywhere inside a value. The search runs against the whole table, so it is not limited to the page you are on.

Why did the preview jump back to the first page?

The preview returns to the first page whenever the search, a filter or the sort changes, so you always see the start of the new query.

Can I put two filters on one column?

No. Each column carries a single filter in a preview. To match several values, tick them all in the column's menu.

How do I find rows where a column has no value?

Open the column's filter menu and choose the empty entry. A blank selection filters for the empty value.

Why did another column's filter change what my filter menu offers?

Filter menus cascade. Each menu offers the values that exist under the other columns' active filters and your search, so filtering one column narrows the others. Changing a filter reloads the lists.

Does a preview download follow my search, filters and sort?

Yes. A preview download is built from the same search, filters and sort as the grid, so your choices carry into the file.

Why do list values look different in an Excel download?

In an Excel download, a column that holds a list is rewritten from its raw form to plain text, in the form a, b, c. The other formats are not rewritten.

Is there a row limit on a preview?

Page sizes stop at 500 rows, and a preview request is capped at 1,000 rows.

Why is my downloaded file named after the table?

Downloads follow the popup's name, and a download from the Source side adds _Source. When the popup has no name of its own, the file falls back to the table's id, such as table_123.

Why is the source preview empty?

The Source side loads only when DataMind can resolve the table's source: its datasource, database and schema. When it cannot, nothing is fetched and the grid stays empty.

What if a filter menu cannot load its values?

Open the menu again to retry. Changing another column's filter, or the search, also reloads the lists. If it keeps failing, reload the preview and try once more.