gadwall - Command Line Client to duckdb

gadwall is a pure Python based command line to duckdb.

It is forked from gadwall, which is available on PyPi - this project is not listed there.

This fork is mainly amended in three ways:

• the output is somewhat tabular
• it can dump its results to an HTML file
• "special" commands, which are not immedialtely passed to duckdb, are prefixed "."

gadwall can:	gadwall can not:
connect to an existing, file based duckdb database	use an in-memory-database
run queries against that database	be installed from PyPi / using pip
create an HTML output of the query results	create a database
show explain plans nicely	show explain plans flawless in HTML output
	deal with every datatype supported by duckdb (try explicitely casting the results to varchar if you have issues; this is basically no limitation of gadwall but of the Python API of duckdb)
	deal with every error from duckdb
	run scripts

image from wikimedia

Example Usage

C:\temp>python gadwall.py sample.db
Welcome to the gadwall, a duckdb shell. Type help or ? to list commands.

duckdb> .html duckdb.html
writing following commands to: "duckdb.html"
duckdb> .db
database: sample.db
duckdb> .schema
+--------+
|name    |
+--------+
|weekdays|
+--------+
duckdb> .schema weekdays
+---+--------+-------+-------+----------+-----+
|cid|name    |type   |notnull|dflt_value|pk   |
+---+--------+-------+-------+----------+-----+
|  0|no      |INTEGER|False  |(NULL)    |False|
|  1|language|VARCHAR|False  |(NULL)    |False|
|  2|label   |VARCHAR|False  |(NULL)    |False|
+---+--------+-------+-------+----------+-----+
duckdb> select * from weekdays
+--+--------+----------+
|no|language|label     |
+--+--------+----------+
| 0|en      |Monday    |
| 1|en      |Tuesday   |
| 2|en      |Wednesday |
| 3|en      |Thursday  |
| 4|en      |Friday    |
| 5|en      |Saturday  |
| 6|en      |Sunday    |
| 0|de      |Montag    |
| 1|de      |Dienstag  |
| 2|de      |Mittwoch  |
| 3|de      |Donnerstag|
| 4|de      |Freitag   |
| 5|de      |Samstag   |
| 6|de      |Sonntag   |
+--+--------+----------+
duckdb> .html off
html file "duckdb.html" closed
duckdb> quit