How to use schemacrawler to generate schema diagrams for SQLite from the commandline (Mac OS)

schemacrawler-sqlite-macos-howto.md

Installing and using schemacrawler for MacOS

A recipe for generating cool SQLite database diagrams with schemacrawler on MacOS

This was tested on MacOS 10.14.5 on 2019-07-16

schemacrawler is a free and open-source database schema discovery and comprehension tool. It can be invoked from the command-line to produce, using GraphViz, images/pdfs from a SQLite (or other database type) file. It can be used from the command-line to generate schema diagrams like these:

To see more examples of commands and diagrams, visit scheacrawler's docs: http://www.schemacrawler.com/diagramming.html

Install graphviz dependency

For schema drawing, schemacrawler uses graphviz, which can be installed via the Homebrew package manager:

brew install graphviz

Installing schemacrawler as a command-line tool

This section gives an example of how to install schemacrawler so that you can invoke it with your shell. There isn't a Homebrew recipe, so the shell commands basically:

• Download a release zip from schemacrawler/releases
• Copies the relevant subdir from the release into a local directory, e.g. /usr/local/opt/schemacrawler
• Creates a simple shell script that saves you from having to run schemacrawler via the java executable
• symlinks this shell script into an executable path, e.g. /usr/local/bin

Downloading and installing schemacrawler

The latest releases can be found on the Github page:

https://github.com/schemacrawler/SchemaCrawler/releases/

Setting up schemacrawler to run on your system via $ schemacrawler

In this gist, I've attached a shell script script-schemacrawler-on-macos.sh that automates the downloading of the schemacrawler ZIP file from its Github repo, installs it, creates a helper script, and creates a symlink to that helper script so you can invoke it via:

$ schemacrawler ...

You can copy the script into a file and invoke it, or copy-paste it directly into Bash. Obviously, as with anything you copy-paste, read it for yourself to make sure I'm not attempting to do something malicious.

(An older version of this script can be found here)

A couple of notes about

The script script-schemacrawler-on-macos.sh has a few defaults – e.g. /usr/local/opt/ and /usr/local/bin/ – which are assumed to be writeable, but you can change those default vars for yourself.

One of the effects of is that it creates a Bash script named something like

Its contents are:

This script is a derivation of schemacrawler's schemacrawler-distrib/src/assembly/schemacrawler.sh, the contents of which are:

General usage

Now that schemacrawler is installed as an executable shell command, here's an example of how to invoke it – change DBNAME.sqlite and OUTPUT_IMAGE_FILE.png to something appropriate for your usecase:

  schemacrawler -server sqlite \
    -database DBNAME.sqlite \
    -user -password \
    -infolevel standard \
    -command schema \
    -outputformat png \
    -outputfile OUTPUT_IMAGE_FILE.png

Bootload a sample SQLite database and test out schemacrawler

Just in case you don't have a database to play around with, you can copy paste this sequence of SQLite commands into your Bash shell, which will create the following empty database file at /tmp/tmpdb.sqlite

echo '''
DROP TABLE IF EXISTS business;
DROP TABLE IF EXISTS inspection;
DROP TABLE IF EXISTS violation;

CREATE TABLE business (
    business_id TEXT,
    name TEXT,
    address TEXT,
    city TEXT,
    postal_code TEXT,
    latitude DECIMAL,
    longitude DECIMAL,
    phone_number TEXT,
    application_date TEXT,
    owner_name TEXT
);

CREATE TABLE inspection (
    business_id TEXT,
    "Score" NUMERIC,
    date TEXT NOT NULL,
    type TEXT NOT NULL,
    FOREIGN KEY(business_id) REFERENCES business(business_id)
);

CREATE TABLE violation (
    business_id TEXT,
    date TEXT,
    "ViolationTypeID" TEXT,
    risk_category TEXT,
    description TEXT,
    FOREIGN KEY(business_id, date) REFERENCES inspection(business_id, date)
);''' \
  | sqlite3 /tmp/tmpdb.sqlite

Invoke schemacrawler like so:

schemacrawler -server sqlite \
  -database /tmp/tmpdb.sqlite \
  -user -password \
  -infolevel standard \
  -command schema \
  -outputformat png \
  -outputfile /tmp/mytmpdb.png

The output of that Bash command will be a file /tmp/tmpdb.sqlite, which looks like this:

GraphViz visual properties

You can edit schemacrawler.config.properties, which is found wherever you installed the schemacrawler distribution – e.g. if you ran my installer script, it would be in /usr/local/opt/schemacrawler/config/schemacrawler.config.properties

Some example settings:

schemacrawler.format.no_schemacrawler_info=true
schemacrawler.format.show_database_info=true
schemacrawler.format.show_row_counts=true
schemacrawler.format.identifier_quoting_strategy=quote_if_special_characters

schemacrawler.graph.graphviz.nodes.ranksep=circo
schemacrawler.graph.graphviz.graph.layout=circo
schemacrawler.graph.graphviz.graph.splines=ortho


schemacrawler.graph.graphviz.node.shape=folder
schemacrawler.graph.graphviz.node.style=rounded,filled
schemacrawler.graph.graphviz.node.fillcolor=#fcfdfc
#schemacrawler.graph.graphviz.node.color=red

schemacrawler.graph.graphviz.graph.fontname=Helvetica Neue
schemacrawler.graph.graphviz.node.fontname=Consolas
schemacrawler.graph.graphviz.edge.fontname=Consolas
schemacrawler.graph.graphviz.edge.arrowsize=1.5

If you append the previous snippet to the default schemacrawler.config.properties, you'll get output that looks like this:

More info about GraphViz in this StackOverflow Q:

How to influence layout of graph items?

script-schemacrawler-on-macos.sh

#!/bin/sh
## Tested on MacOS 10.14.5
## Gist URL: https://gist.github.com/dannguyen/f056d05bb7fec408bb7c14ea1552c349

########################
# Variables and defaults
########################

# Modify this for whatever version you're trying to download
_SCH_VERSION='15.06.01'

# Pick your own temp dir
# Note that the zip archive by default creates and unzips into a subdir,
#   e.g. `schemacrawler-15.06.01-distribution`
_TEMPDIR=/tmp

# Pick the path to store the app and the shell script
# NOTE: The parent dir – e.g. /usr/local/opt – must be writable
_INSTALL_DIR=/usr/local/opt/schemacrawler

# Pick the symlink for the path; ideally, it's a path that is in your system's executable PATH
# NOTE: The executable PATH – e.g. /usr/local/bin – must be writable
_SCH_SYMLINK=/usr/local/bin/schemacrawler


#####
# These defaults are derived from above

# The filename stem for the downloadable zip, as it exists on the Github filesystem,
#   and the subdir it creates when unzipped
_SCH_FNAME="schemacrawler-${_SCH_VERSION}-distribution"
_SCH_URL="https://github.com/schemacrawler/SchemaCrawler/releases/download/v${_SCH_VERSION}/${_SCH_FNAME}.zip"
_SCH_ZNAME="${_TEMPDIR}/${_SCH_FNAME}.zip"
# `schema-macos-opt.sh` is just the arbitrary name from which the symlink will be based
_SCH_SCRIPT_NAME="${_INSTALL_DIR}/schemacrawler-macos-opt.sh"


#########
# Actions
#########

# Download and unzip into $_TEMPDIR
mkdir -p ${_TEMPDIR}
printf "\nDownloading\n\t ${_SCH_URL} \n\tinto temporary directory: ${_TEMPDIR}\n\n"
curl -Lo ${_SCH_ZNAME} ${_SCH_URL}
unzip ${_SCH_ZNAME} -d ${_TEMPDIR}
printf "\n\n"

# Move subdir from release package into /usr/local/opt
printf "\nMoving contents of /tmp/${_SCH_FNAME}/_schemacrawler/ \n\tinto ${_INSTALL_DIR}"
mkdir -p ${_INSTALL_DIR}
cp -r /tmp/${_SCH_FNAME}/_schemacrawler/ ${_INSTALL_DIR}

# create the shell script manually
# https://stackoverflow.com/questions/2953081/how-can-i-write-a-heredoc-to-a-file-in-bash-script
printf "\n\nCreating ${_SCH_SCRIPT_NAME}"

# The shell code below is a variation of what's found at:
# https://github.com/schemacrawler/SchemaCrawler/blob/a3fea8be74ae28d6e8318c14f2c3f4be314efe2a/schemacrawler-distrib/src/assembly/schemacrawler.sh
cat << SCSCRIPT > ${_SCH_SCRIPT_NAME}
#!/usr/bin/env bash
SCHEMACRAWL_DIR=${_INSTALL_DIR}
java -cp \$(echo \${SCHEMACRAWL_DIR}/lib/*.jar | tr ' ' ':'):\${SCHEMACRAWL_DIR}/config schemacrawler.Main "\$@"
SCSCRIPT

# make the shell script executable and symlink it
printf "\n\nSymlinking ${_SCH_SCRIPT_NAME} \n\tto ${_SCH_SYMLINK}\n\n"
chmod +x ${_SCH_SCRIPT_NAME}
ln -sf ${_SCH_SCRIPT_NAME} ${_SCH_SYMLINK}

script_OLD-schemacrawler-on-macos.sh

# This was tested on MacOS 10.13

# set up some variables to reduce redundancy

_SCH_VERSION='14.21.02'
_SCH_BNAME="schemacrawler-${_SCH_VERSION}-distribution"
_SCH_TNAME="/tmp/${SCH_BNAME}.zip"
_SCH_URL="https://github.com/schemacrawler/SchemaCrawler/releases/download/v${_SCH_VERSION}/${_SCH_BNAME}.zip"
_SCH_DIR='/usr/local/opt/schemacrawler'
_SCH_SH="${_SCH_DIR}/schemacrawler-macos-opt.sh"

# Download and unzip into /tmp
curl -Lo ${_SCH_TNAME} ${_SCH_URL}
unzip ${_SCH_TNAME}

# Move subdir from release package into /usr/local/opt
mkdir -p ${_SCH_DIR}
cp -r /tmp/${_SCH_BNAME}/_schemacrawler/ ${_SCH_DIR}

# create the shell script manually
echo '#!/usr/bin/env bash' > ${_SCH_SH}
echo "SC_DIR=${_SCH_DIR}" >> ${_SCH_SH}
echo "java -cp \$(echo \$SC_DIR/lib/*.jar | tr ' ' ':'):\$SC_DIR/config schemacrawler.Main \"\$@\"" \
  >> ${_SCH_SH}

# make it executable and symlink it

chmod +x ${_SCH_SH}
ln -sf ${_SCH_SH} /usr/local/bin/schemacrawler  

You'd never know this would help someone random like me, but it was the only thing that helped a random person like me, so thank you. <3

This was very helpful to this rando as well

<3

Nice guide, thank you!

(part of the comment is removed, since is not actual anymore)

@PavelPolyakov thanks! Looks like I also needed to run unzip with the -d ${TEMPDIR} flag so that it wouldn't install to wherever you were running the commands. Created an updated version of the script to reflect this.

@dannguyen cool, I suggest we remove the old ones to not confuse people

👍 I forgot to chmod 744 the script file at first and was banging my head for a minute.

is there a way to use this on windows 10 ?