PB DW form under the select nested fields can be single, if you have multiple lines, how to deal with?
Similar to the select Anderson d,
A.n ame,
(select id_code from b where XXX) id_code,
XXXXXX
.



(select id_code from b where XXX) id_code, like the nested fields, if is how to deal with?

CodePudding user response:

Advanced, didn't understand

CodePudding user response:

(select id_code from b where XXX) id_code
What do you mean this statement of query value when there are multiple?
It is no good, SQL syntax is not allowed to have such a query, the first thing you want to make sure that you write the SQL statements are correct,

Subquery returns the value of more than one, when the query to follow in=,!=, & lt; , & lt;=, & gt; ,>=, or the subquery is used as the expression, the situation is not allowed,

(select top 1 id_code from b where XXX) id_code

CodePudding user response:

With the joint statement is ok, it is very convenient

CodePudding user response:

Embedded within the cover of the SQL query only returns the data line, if the nested children query returns multiple lines will be an error, so I want to solve the problem is not nesting child query can solve the problem,

If you want to express the main query and the subquery data is a one-to-many relationship between father and son, and through the datawindow first the data display, two data can be associated, with treedatawindow display can solve this problem,