RDBMS Sampler

Command line utility for extracting a sample (subset of all records) from a relational database system (such as MySQL) while maintaining the referential integrity of the sample.

Need e.g. 1000 rows from each of your production tables, but feel the pain of making sure to include dependent rows, their dependents and so on, ad infinitum?

Look no further. This tiny utility will take care that referential dependencies are fulfilled by recursively expanding the row sample with unfilled dependencies until the sample is referentially consistent.

Install with gem install rdbms_sampler.

Alternatively, clone the repository and install dependencies with bundle install. Then execute with bundle exec rdbms_sampler ....

help        Display global or [command] help documentation.
sample      Extract a sample from the given connection

--adapter NAME
    ActiveRecord adapter to use

--databases NAMES
    Comma-separated list of databases to sample

--username USER
    Username for connection

--password PASSWORD
    Password for connection

--encoding ENCODING
    Encoding for connection

--host HOST
    Host name or IP for connection

--socket PATH
    Socket for connection

--rows NUM
    Number of rows to sample per table

--log PATH
    Log queries to PATH

-h, --help
    Display help documentation

-v, --version
    Display version information

-t, --trace
    Display backtrace when an error occurs

rdbms_sampler --databases DB1,DB2 --username USER --password PASS --rows 100 > sample.sql

Only single-column foreign keys are currently handled.

Additionally, due to a bug in the current implementation, if a referenced column is named anything but id, referenced rows might get included multiple times.

You will probably need to disable foreign key check during import, since inserts in the output are not ordered with respect to referential integrity.