Module: JdbcSpec::MsSQL::SqlServerLimitOffset

Defined in:
lib/jdbc_adapter/jdbc_mssql.rb

Instance Method Summary collapse

Instance Method Details

#add_limit_offset!(sql, options) ⇒ Object



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# File 'lib/jdbc_adapter/jdbc_mssql.rb', line 235

def add_limit_offset!(sql, options)
  limit = options[:limit]
  if limit
    offset = (options[:offset] || 0).to_i
    start_row = offset + 1
    end_row = offset + limit.to_i
    order = (options[:order] || determine_order_clause(sql))
    sql.sub!(/ ORDER BY.*$/i, '')
    find_select = /\b(SELECT(?:\s+DISTINCT)?)\b(.*)/i
    whole, select, rest_of_query = find_select.match(sql).to_a
    new_sql = "#{select} t.* FROM (SELECT ROW_NUMBER() OVER(ORDER BY #{order}) AS row_num, #{rest_of_query}"
    new_sql << ") AS t WHERE t.row_num BETWEEN #{start_row.to_s} AND #{end_row.to_s}"
    sql.replace(new_sql)
  end
end