maxgronlund / data_sampler

Extract a sample of records from a database while ensuring referential integrity

data_sampler

A Ruby command line utility for extracting a sample of records from a relational database system (such as MySQL) while maintaining referential integrity in 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.

COMMANDS

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

OPTIONS

--adapter NAME
    ActiveRecord adapter to use

--database NAME
    Name of database to sample

--username USER
    Username for connection

--password PASSWORD
    Password for connection

--encoding ENCODING
    Encoding for connection

--socket PATH
    Socket for connection

--rows NUM
    Number of rows to sample per table

--log PATH
    Log queries to PATH

GLOBAL OPTIONS

-h, --help
    Display help documentation

-v, --version
    Display version information

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

USAGE

data_sampler --database SOME_LEGACY_DB --username MY_USER --password MY_PASS --rows 100 > sample.sql

CAVEATS

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