If you’re getting an error that reads “mode should be one of: ascii box column …etc” in DuckDB, it appears that you’re trying to set the output mode to an invalid value.

While we can change the output mode in DuckDB, it must be one of the supported modes.

To fix this issue, be sure to use a supported mode.

Example of Error

Here’s an example of code that produces the error:

.mode default

Output:

Error: mode should be one of: ascii box column csv duckbox html insert json jsonlines latex line list markdown quote table tabs tcl trash

Here I tried to change the output mode to default, but DuckDB doesn’t support that value.

Solution

To fix this issue, use one of the output modes that DuckDB supports. Fortunately the error message shows us which values are supported, so we can use one of those.

Example:

.mode duckbox

In this case, no error was returned. That’s because I changed the mode to a supported mode, in this case duckbox, which is DuckDB’s default mode.

Get a List of Supported Modes

You can use the following command to get a list of supported modes:

.help mode

Output:

.mode MODE ?TABLE?       Set output mode
   MODE is one of:
     ascii     Columns/rows delimited by 0x1F and 0x1E
     box       Tables using unicode box-drawing characters
     csv       Comma-separated values
     column    Output in columns.  (See .width)
     duckbox   Tables with extensive features
     html      HTML <table> code
     insert    SQL insert statements for TABLE
     json      Results in a JSON array
     jsonlines Results in a NDJSON
     latex     LaTeX tabular environment code
     line      One value per line
     list      Values delimited by "|"
     markdown  Markdown table format
     quote     Escape answers as for SQL
     table     ASCII-art table
     tabs      Tab-separated values
     tcl       TCL list elements
     trash     No output

This shows us the syntax, followed by the supported modes.