vf query results are empty tables, and vf uses SQL to query the empty tables

select class.Class number, classClass name, studentName as Class Leader's Name,;

teacher.Teacher's name as class teacher's name;

from sdb!student inner join sdb!class;

inner join sdb!teacher ;

on teacher.Teacher number in (class.Class Teacher No.);

on student.Student ID in (class.Squad Leader) That's right.

Each join is followed by an on, rather than multiple joins followed by multiple on:

select class.Class number, classClass name, studentName as Class Leader's Name,;

teacher.Teacher's name as class teacher's name;

from sdb!student ;

inner join class on student.Student ID = classsquad leader;

inner join teacher on class.Class Teacher Number = TeacherTeacher's number.

Can't you just copy it? select b.Class number, AClass name, bName Squad Leader's Name, CTeacher's name Homeroom teacher's name from ;

class a left join student b on a.Squad Trombone = BStudent ID ;

left join teacher c on a.Class teacher number = cTeacher's number.

order by b.Class number ASC into Table One

There are only two possibilities.

One is that there is no record in the data table that meets the conditions, and the result must be an empty table.

There are two types of errors, one is grammatical error and the other is semantic error. If the syntax is wrong, the command will definitely not be executed. That must be a mistake in the semantic meaning of the fan, to see if it meets the requirements of the question or the conditions are wrong.

That is, the sql command cannot query the records that meet the conditions, that is, the conditions you give cannot query the corresponding records, such as the maximum age field in the table is 50 years old, and the result condition is set to age" 60, you will definitely not be able to find the record.

If the search result is an empty set, an empty table will appear, and see if the condition is written incorrectly.

Now that the table is out, it turns out that there are no errors in the syntax, and that there is no data because no matching conditions were found, check your query criteria. It won't even be selete * without anything, right?

If there is a problem with the SQL statement, print out the SQL statement and take a look.

Checking where to go? Does it mean putting the query results into a table?

If the destination table does not exist, you should create the target table and then insert the query results into it.

3. Focus on mastering the single index file, and do not require the order parameter to open the index: (1) Open it with the table (Design a menu named CX3, and there are two menu items in the menu: "query" and "exit"). Procedure,

You don't need to create, it can be generated automatically... This source file doesn't exist, so I don't understand it.

Let's just say an example: Suppose the data environment adds a table that displays the name and gender fields in **.

**The name of the control is the default grid1, select 4 in the recordsourcetype property of grid1--- sql description, and the click event of the command button command1 can be written like this:

Sele Name, Gender from TS Into Cursor ABC"

1.Add a wait window to the two cases to check whether there are any records that meet the conditions.

2.If the above conditions are met, you can manually select *;

from Teacher's Table;

where salary order by salary desc, name to see if there is any information.

The above is the way I thought of finding the problem after seeing **. Hope it helps.