Използване на MySQL GROUP_CONCAT или PIVOT върху множество свързани таблици

Ето макет-PIVOT прилагане на rownum до учителите:

select s.col_entry,
  max(case when s.col_inquiry_name = 'Title' then s.col_value end) AS 'Title',
  max(case when s.col_inquiry_name = 'Course' then s.col_value end) AS 'Course',
  max(case when b.col_inquiry_name = 'Description' then b.col_value end) AS 'Description',
  max(case when d.col_inquiry_name = 'Semester' then d.col_value end) AS 'Semester',
  max(case when s.col_inquiry_name = 'Location' then s.col_value end) AS 'Location',
  max(case when tch.grp = 'Teachers_01' then tch.col_value end) AS 'Teachers_01',
  max(case when tch.grp = 'Teachers_02' then tch.col_value end) AS 'Teachers_02',
  max(case when tch.grp = 'Teachers_03' then tch.col_value end) AS 'Teachers_03',
  max(case when tch.grp = 'Teachers_04' then tch.col_value end) AS 'Teachers_04',
  max(case when tch.grp = 'Teachers_05' then tch.col_value end) AS 'Teachers_05'
from smallText s
left join bigText b
  on s.col_entry = b.col_entry 
left join date d
  on b.col_entry = d.col_entry 
left join
(
  select col_entry, col_value, concat('Teachers_0', group_row_number) grp
  from
  (
    select col_entry, col_value,
      @num := if(@col_entry = `col_entry`, @num + 1, 1) as group_row_number,
      @col_entry := `col_entry` as dummy
    from smallText , (SELECT @rn:=0) r
    where col_inquiry_name = 'Teachers'
      and col_value != ''
  ) x
) tch
  on s.col_entry = tch.col_entry
group by s.col_entry;

вижте SQL Fiddle с демонстрация

Редактирайте #1 въз основа на допълнителното поле, което сте предоставили col_order можете да го използвате, за да определите учителите, без да използвате rownum променливи:

select s.col_entry,
  max(case when s.col_inquiry_name = 'Title' then s.col_value end) AS 'Title',
  max(case when s.col_inquiry_name = 'Course' then s.col_value end) AS 'Course',
  max(case when b.col_inquiry_name = 'Description' then b.col_value end) AS 'Description',
  max(case when d.col_inquiry_name = 'Semester' then d.col_value end) AS 'Semester',
  max(case when s.col_inquiry_name = 'Location' then s.col_value end) AS 'Location',
  max(case when s.col_inquiry_name = 'Teachers'
        and s.col_order = 1 then s.col_value end) AS 'Teachers_01',
  max(case when s.col_inquiry_name = 'Teachers'
        and s.col_order = 2 then s.col_value end) AS 'Teachers_02',
  max(case when s.col_inquiry_name = 'Teachers'
        and s.col_order = 3 then s.col_value end) AS 'Teachers_03',
  max(case when s.col_inquiry_name = 'Teachers'
        and s.col_order = 4 then s.col_value end) AS 'Teachers_04',
  max(case when s.col_inquiry_name = 'Teachers'
        and s.col_order = 5 then s.col_value end) AS 'Teachers_05'
from smallText s
left join bigText b
  on s.col_entry = b.col_entry 
left join date d
  on b.col_entry = d.col_entry 
group by s.col_entry

вижте SQL Fiddle с демонстрация