使用TSQL分離行成多行

Question

我期待編寫一個腳本，將改變表1至表2

表1

AccountNo名稱等領域

1  Mr T and Mrs M Lambert  xxx 

我需要將其重寫爲

表2

AccountNo分裂名稱等領域

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

Answer 1

如果我是你，我會採取一些選擇的腳本語言編寫，並用其援助的轉換器。對我來說，看起來Perl或Ruby很適合這項任務。

例如，在Ruby中，這可能是這樣的：

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 

毫無疑問，它可以在SQL中實現，尤其是在像PL/SQL更豐富的方言，但文本分析（你顯然會相當做這裏有很多）並不是SQL強大的一面。因此，您將花費大量時間用不適合他們的語言來計算字符串操作。

希望有幫助！

Answer 2

您只需將from子句更改爲您的表名稱即可。

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 

結果：

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