Question

我希望编写一个将表1更改为表2的脚本。

表1

AccountNo命名其他字段

   1      Mr T and Mrs M Lambert      xxx

我需要将其重写为

表2

AccountNo拆分名称其他字段

   1       a          Mr T Lambert             xxx
   1       b          Mrs M Lambert            xxx

Answer 1

如果我是你，我会选择一些脚本语言并在其帮助下编写转换器。对我而言，看起来Perl或Ruby非常适合这项任务。

例如，在Ruby中，这可能是：

require 'active_record'

ActiveRecord::Base.establish_connection('postgresql://localhost/db')
sql = ActiveRecord::Base.connection

sql.begin_db_transaction

# fetch the data from the source table
sql.execute('SELECT * FROM source_table').each do |source_row|
  # source_row is a hash now of the following form:
  # { 'col_name_1' => 'col_value_1', 'col_name_2' => ... }

  # prepare transformed rows array that will result in the destination table
  transformed_rows = [ ]

  # make up all the transformed rows you need, based on the source fields
  transformed_rows << {
    'another_col_1' => source_row['col_name_1'],
    # ...
  }

  transformed_rows.each do |transformed_row|
    # generate and execute the insert statement for every transformed_row
    sql.execute("INSERT INTO destination_table(...) VALUES(...)")
  end
end

sql.commit_db_transaction

毫无疑问，它可以在SQL中实现，特别是在PL / SQL等更丰富的方言中，但是文本解析（这显然你会在这里做很多事情）并不是SQL强大的一面。因此，您将花费大量时间用不太适合它们的语言来计算字符串操作。

希望有所帮助！

Answer 2

您所要做的就是将from子句更改为您的表名，它应该可以正常工作。

SELECT  AccountNo,
        person,
        other
FROM (VALUES(1,'Mr T and Mrs M Lambert','xxx')) AS yourTable (AccountNo,Name,Other)
CROSS APPLY (SELECT REVERSE(SUBSTRING(REVERSE(Name),0,CHARINDEX(' ',REVERSE(name))))) CA(lastName)
CROSS APPLY (
                SELECT PARSENAME(REPLACE(name,' and ','.'),1) person --first person
                UNION ALL 
                SELECT PARSENAME(REPLACE(name,' and ','.'),2) + ' ' +  lastName --second person
             ) CA2

结果：

AccountNo   person                                                                                                                                                  other
----------- ------------------------------------------------------------------------------------------------------------------------------------------------------- -----
1           Mrs M Lambert                                                                                                                                           xxx
1           Mr T Lambert                                                                                                                                            xxx

使用tsql拆分行成多行

2 个答案: