Class: Ductr::SQLite::BasicLookup

Inherits:
ETL::Transform
  • Object
show all
Defined in:
lib/ductr/sqlite/basic_lookup.rb

Overview

A lookup control that execute one query per row, registered as :basic. The job's method must return a row which will merged with the current row:

lookup :some_sqlite_database, :basic def my_lookup(db, row) db[:items_bis].where(item: row[:id]).limit(1) end

As the control merge the looked up row with the current row, ensure that column names are different or they will be overwritten.

If the lookup returns a falsy value, nothing won't be merged with the current row.

Instance Method Summary collapse

Instance Method Details

#process(row) ⇒ Hash<Symbol, Object>

Calls the job's method to merge its result with the current row.

Parameters:

  • row (Hash<Symbol, Object>) —

    The current row, preferably a Hash

Returns:

  • (Hash<Symbol, Object>) —

    The row merged with looked up row or the untouched row if nothing was found



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# File 'lib/ductr/sqlite/basic_lookup.rb', line 29

def process(row)
  matching_row = call_method(adapter.db, row).first
  return row unless matching_row

  row.merge matching_row
end