...Can you please share what you exactly did to get that nice horizontal diagram?

I'm interested in this too, but until someone works up a viable pull request for this, you can do the following crappy ad hoc solution: modify the global value GRAPH_BEGINNING which can be found in the project's eralchemy/eralchemy/cst.py file.

What to do:

You can do this programmatically if you want to dirty your hands with building eralchemy's Abstract Syntax Tree (AST) at runtime. This would see you build the AST, then modify the rvalue of the GRAPH_BEGINNING member, then overwrite the cst.py file with the updated AST. But if you just want a quick and easy solution, you can just navigate to the file manually and make the modifications in a text editor ;).

Here's the steps to the easy approach:

GRAPH_BEGINNING sets up instructions that pygraphviz uses in configuring the graph image. As such it specifies properties like rankdir. You will want to modify the value assigned to rankdir to be TB in order to get output like what is seen in the final image from OP.

Here's the literal example:

contents of ~/eralchemy/cst.py

# -*- coding: utf-8 -*-

"""
All the constants used in the module.
"""
TABLE = '"{}" [label=<<FONT FACE="Helvetica"><TABLE BORDER="0" CELLBORDER="1"' \
        ' CELLPADDING="4" CELLSPACING="0">{}{}</TABLE></FONT>>];'

START_CELL = '<TR><TD ALIGN="LEFT"><FONT>'
FONT_TAGS = '<FONT>{}</FONT>'
# Used for each row in the table.
ROW_TAGS = '<TR><TD{}>{}</TD></TR>'
# commenting out original value of GRAPH_BEGINNING
# GRAPH_BEGINNING = (' graph {\n'
#                    '    graph [rankdir=LR];\n' # notice that rankdir=LR is the `eralchemy` default
#                    '    node [label=\"\\N\",\n'
#                    '        shape=plaintext\n'
#                    '    ];\n'
#                    '    edge [color=gray50,\n'
#                    '        minlen=2,\n'
#                    '        style=dashed\n'
#                    '    ];\n'
#                    )

# And changing it so we get a GraphViz's top-to-bottom ranking of components.
#     NOTE: GraphViz is ignorent of what our tables actually are, 
#                from the GraphViz perspective, our tables are simply nodes.
#
#                The "rank" of a node is determined by the order the nodes are added.
#                This means that if we have 2 related tables, and we want one to appear 
#                beneath the other, we have to add the "lower rank" table after we've 
#                added the "higher rank" table.  
#
#  possible valid values for rankdir are: 
#       TB, BT, LR, RL
#  which correspond to:
#       Top-to-Bottom, Bottom-to-Top, Left-to-Right, Right-to-Left
GRAPH_BEGINNING = (' graph {\n'
                   '    graph [rankdir=TB];\n' # and here we are changing it to be rankdir=TB
                   '    node [label=\"\\N\",\n'
                   '        shape=plaintext\n'
                   '    ];\n'
                   '    edge [color=gray50,\n'
                   '        minlen=2,\n'
                   '        style=dashed\n'
                   '    ];\n'
                   )

Bumps ws from 6.2.1 to 6.2.2. <details> <summary>Commits</summary> <ul> <li>See full diff in <a href="https://github.com/websockets/ws/commits">compare view</a></li> </ul> </details> <br />

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

<details> <summary>Dependabot commands and options</summary> <br />

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot close will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
• @dependabot use these labels will set the current labels as the default for future PRs for this repo and language
• @dependabot use these reviewers will set the current reviewers as the default for future PRs for this repo and language
• @dependabot use these assignees will set the current assignees as the default for future PRs for this repo and language
• @dependabot use this milestone will set the current milestone as the default for future PRs for this repo and language

You can disable automated security fix PRs for this repo from the Security Alerts page.

</details>