dql 0.6.2

DynamoDB Query Language

DQL

Build:

Documentation:

http://dql.readthedocs.org/

Downloads:

http://pypi.python.org/pypi/dql

Source:

https://github.com/stevearc/dql

A simple, SQL-ish language for DynamoDB

As of November 2020, Amazon has released PartiQL support for DynamoDB. You should investigate that first to see if it addresses your needs.

Getting Started

Installation can be done in a variety of ways

• An executable pex file is available on the release page.

• You can run a script to generate the pex file yourself: curl -o- install.py https://raw.githubusercontent.com/stevearc/dql/master/bin/install.py | python

• With pip: pip install dql

Examples

Here are some basic DQL examples to get you going:

Start the REPL:

$ dql
us-west-1>

Creating a table:

us-west-1> CREATE TABLE forum_threads (name STRING HASH KEY,
         >                             subject STRING RANGE KEY,
         >                             THROUGHPUT (4, 2));

Inserting data:

us-west-1> INSERT INTO forum_threads (name, subject, views, replies)
         > VALUES ('Self Defense', 'Defense from Banana', 67, 4),
         > ('Self Defense', 'Defense from Strawberry', 10, 0),
         > ('Cheese Shop', 'Anyone seen the camembert?', 16, 1);

Queries:

us-west-1> SCAN * FROM forum_threads;
us-west-1> SELECT count(*) FROM forum_threads WHERE name = 'Self Defense';
us-west-1> SELECT * FROM forum_threads WHERE name = 'Self Defense';

Mutations:

us-west-1> UPDATE forum_threads ADD views 1 WHERE
         > name = 'Self Defense' AND subject = 'Defense from Banana';
us-west-1> DELETE FROM forum_threads WHERE name = 'Cheese Shop';

Changing tables:

us-west-1> ALTER TABLE forum_threads SET THROUGHPUT (8, 4);
us-west-1> DROP TABLE forum_threads;

And don’t forget to use help!

Changelog

0.6.2 - Unreleased

• Fix: Issue with missing dependency (typing_extensions) made apparent by python 3.9

• Added: Run tests with python 3.9

• Chore: general cleanup & lint fixes

• Chore: removing travis-ci; adding github workflows

• Added: clear & cls commands.

• Updated: clear, cls, exit commands are no longer tracked in history.

0.6.1

• Feature: Retain query history across sessions. (#40)

• Fix: Cannot count(*) on an index (#37)

• Fix: Saving data to some file formats was failing

• Fix: Constraint functions accept quoted field names (#36)

• Chore: Updated config for Dynamo Local to install dependency within project root.

0.6.0

• Bug fix: Fixed ZeroDivisionError with ls on On-Demand tables (#32)

• Added: ls command accepts glob patterns (#30)

• Added: Better error handling and display. (#28)

• Added: Standard error handling for execution with -c option. (#28)

• Added: Keyboard interrupts will print spooky emojis. (#28)

• Added: --json argument for use with -c to format results as JSON

• Chore: General Dev Env & CI updates for easier development. (#27)

0.5.28

• Bug fix: Encoding errors for some SAVE file formats

0.5.27

• Bug fix: Proper throttling in Python 3

Dropping support for python 3.4

0.5.26

• Use python-future instead of six as compatibility library

• Now distributing a wheel package

• Bug fix: Confirmation prompts crash on Python 2

0.5.25

• Bug fix: Compatibility errors with Python 3

0.5.24

• Bug fix: Support key conditions where field has a - in the name

0.5.23

• Bug fix: Default encoding error on mac

Dropping support for python 2.6

0.5.22

• Bug fix: Can now run any CLI command using -c "command"

0.5.21

• Bug fix: Crash fix when resizing terminal with ‘watch’ command active

• ‘Watch’ columns will dynamically resize to fit terminal width

0.5.20

• Bug fix: When saving to JSON floats are no longer cast to ints

• Bug fix: Reserved words are correctly substituted when using WHERE … IN

0.5.19

• Locked in the version of pyparsing after 2.1.5 broke compatibility again.

0.5.18

• Bug fix: Correct name substitution/selection logic

• Swapped out bin/run_dql.py for bin/install.py. Similar concept, better execution.

0.5.17

• Bug fix: Can’t display Binary data

0.5.16

• Bug fix: Can’t use boolean values in update statements

0.5.15

• Gracefully handle missing imports on Windows

0.5.14

• Missing curses library won’t cause ImportError

0.5.13

• Fix bug where query would sometimes display ‘No Results’ even when results were found.

0.5.12

• Differentiate LIMIT and SCAN LIMIT

• Options and query syntax for throttling the consumed throughput

• Crash fixes and other small robustness improvements

0.5.11

• SELECT <attributes> can now use full expressions

0.5.10

• LOAD command to insert records from a file created with SELECT ... SAVE

• Default SAVE format is pickle

• SAVE command can gzip the file

0.5.9

• Don’t print results to console when saving to a file

• ‘auto’ pagesize to adapt to terminal height

• When selecting specific attributes with KEYS IN only those attributes are fetched

• ORDER BY queries spanning multiple pages no longer stuck on first page

• Column formatter fits column widths more intelligently

• Smart formatter is smarter about switching to Expanded mode

0.5.8

• Tab completion for Mac OS X

0.5.7

• run_dql.py locks in a version

• Display output auto-detects terminal width

0.5.6

• Format option saves properly

• WHERE expressions can compare fields to fields (e.g. WHERE foo > bar)

• Always perform batch_get after querying/scanning an index that doesn’t project all attributes

0.5.5

• General bug fixes

• Self contained run_dql.py script

0.5.4

• Fixes for watch display

• SELECT can save the results to a file

0.5.3

• ALTER commands can specify IF (NOT) EXISTS

• New watch command to monitor table consumed capacities

• SELECT can fetch attributes that aren’t projected onto the queried index

• SELECT can ORDER BY non-range-key attributes

0.5.2

• EXPLAIN <query> will print out the DynamoDB calls that will be made when you run the query

• ANALYZE <query> will run the query and print out consumed capacity information

0.5.1

• Pretty-format non-item query return values (such as count)

• Disable passing AWS credentials on the command line

0.5.0

• Breakage: New syntax for SELECT, SCAN, UPDATE, DELETE

• Breakage: Removed COUNT query (now SELECT count(*))

• Breakage: Removed the ability to embed python in queries

• New alternative syntax for INSERT

• ALTER can create and drop global indexes

• Queries and updates now use the most recent DynamoDB expressions API

• Unified options in CLI under the opt command

0.4.1

• Update to maintain compatibility with new versions of botocore and dynamo3

• Improving CloudWatch support (which is used to get consumed table capacity)

0.4.0

• Breakage: Dropping support for python 3.2 due to lack of botocore support

• Feature: Support for JSON data types

0.3.2

• Bug fix: Allow ‘.’ in table names of DUMP SCHEMA command

• Bug fix: Passing a port argument to local connection doesn’t crash

• Bug fix: Prompt says ‘localhost’ when connected to DynamoDB local

0.3.1

• Bug fix: Allow ‘.’ in table names

0.3.0

• Feature: SELECT and COUNT can have FILTER clause

• Feature: FILTER clause may OR constraints together

0.2.1

• Bug fix: Crash when printing ‘COUNT’ queries

0.2.0

• Feature: Python 3 support

0.1.0

• First public release