Generate an E-R Diagram by reverse-engineering a database [closed]

Answer 1

Microsoft Visio will easily do this.

Answer 2

Dot is part of the graphviz package, which is a pretty damn cool/useful tool. Of course, you'll need something to generate the dot files for graphviz. I've used SchemaSpy once or twice in the past, and it works pretty well, provided you have the relationships defined in the database.

Answer 3

Dot is multiplatform and may be useful.

Answer 4

DBVisualizer is also a free and nice alternative.

Answer 5

At least for Oracle I run this query or ask the DBA to run it and send me the results. Results can be copied directly to a text file to be interpreted by Graphviz's tools, resulting in a database diagram.

SELECT '"' || Source.TABLE_NAME || '" -> "' 
           || Destiny.TABLE_NAME || '";' AS For_GraphViz
FROM dba_constraints Source
JOIN dba_constraints Destiny
ON Source.owner='my_db_owner' AND Destiny.owner='my_db_owner'
AND Source.CONSTRAINT_TYPE='R'
-- theoretically this validation should be redundant
-- AND Destiny.Constraint_type = 'P'
AND Source.R_CONSTRAINT_NAME = Destiny.CONSTRAINT_NAME
ORDER BY Source.TABLE_NAME, Source.CONSTRAINT_TYPE, Source.CONSTRAINT_NAME
    , Source.R_CONSTRAINT_NAME, Source.INDEX_NAME;

A similar query can be created easily for SQL Server, don't know about MySQL, PostgreSQL et al.