Question

我有3个表table_1，table_2和table_3。

我正在尝试通过table_1和table_2的连接在table_3中插入数据（该表中已经存在一些行）。

table_3 has following columns:

unique_id  - its unique id needs to be increment by 1 from its last value
client_key - should get from table_1.client_key
xcolumn    - should get from table_2.xcolumn
xxcolumn   - this column value depend on table_3.xcolumn (below I mentioned which value should be here) 
         if table_3.xcolumn contains any of this value (purchase some things,purchase) xxcolumn should be PURCHASE 
         if table_3.xcolumn contains any of this value (cash advance,ATM,promo cashing) xxcolumn should be CASH
         if table_3.xcolumn contains any of this value (promo,promo deal) xxcolumn should be PROMO
         if table_3.xcolumn doest not contains any above value then xxcolumn should be OTHER
xycolumn   - this column value depend on table_3.xxcolumn (below I mentioned which value should be here)
         if table_3.xxcolumn is PURCHASE xycolumn should be 1 
         if table_3.xxcolumn is CASH xycolumn should be 2
         if table_3.xxcolumn is PROMO xycolumn should be 3
         if table_3.xxcolumn is OTHER xycolumn should be 4           
ycolumn    - should get from table_2.ycolumn

我已经尝试过以下查询插入内容：

insert into table_3(unique_id,client_key,xcolumn,xxcolumn,xycolumn,ycolumn)  
select (select max(unique_id) + 1 from 
table_3),table_1.client_key,table_2.xcolumn,'cash',1,table_2.ycolumn from 
table_2  inner join table_1 on table_2.client_id=table_1.client_id;

但是对于unique_id，如果获得多于一行的行，我将无法在连接时将其值增加1（仅对所有行不起作用一次）

我也无法弄清楚如何获得xxcolumn，xycolumn值。

参考我用table_1，table_2，，table_3

创建了sql小提琴

http://sqlfiddle.com/#!9/8a48477/2

插入时将列值增加1。

0 个答案: