I want to update the values of a column with the name of a related entry appended with a number for each row. I've seen a couple of other questions which give roughly the same answer, but when I try the below, I get NULL added instead.
SET #i = 0;
UPDATE matrix_data md
SET col_id_4 = concat((SELECT title from titles t WHERE t.entry_id = md.entry_id), (#i:=#i+1));
If I replace (#i:=#i+1) with a static value, then the update works OK.
The col_id_4 column is set to text. Does the above only work with numeric column types? And if so, how do I achieve what I want to do?
How about you take the primary key of the titles table instead of using the iterator, thus filling in col_id_4 with a concatenation of titles.title and titles.entry_id, thus…
UPDATE matrix_data
INNER JOIN titles ON matrix_data.entry_id = titles.entry_id
SET matrix_data.col_id_4 = CONCAT(titles.title, "_", titles.entry_id)
Or maybe it’s a type issue; casting the iterator to char(50) as we concatenate with the string should work. Tested in a rudimentary database, not #craftcms or #eecms specifically.
SET #i := 0;
UPDATE matrix_data
INNER JOIN titles ON matrix_data.entry_id = titles.entry_id
SET matrix_data.col_id_4 = CONCAT(titles.title, "_", CAST(#i := #i + 1 as CHAR(50)))
Related
I need to update a json value in a column as well as update another column in the same query.
Something like this:
UPDATE fixtures
SET jsonResults = '{}',
JSON_SET(jsonFixture, '$.time_status', '0')
WHERE intRefID = 88961323;
How can I accomplish this?
JSON_SET() returns a JSON document value, but an UPDATE statement needs a series of assignment expressions:
UPDATE fixtures
SET jsonResults = '{}',
jsonFixture = JSON_SET(jsonFixture, '$.time_status', '0')
WHERE intRefID = 88961323;
This replaces jsonFixture with the result of JSON_SET(), after setting a field within that document.
Compare with an UPDATE like this:
UPDATE mytable
SET i = i + 1
WHERE ...
It takes the value of i, adds 1, and then uses the result of that addition expression to replace i.
I have lost hours on this and nothing works for me.
I have filed strp_aa that is default NULL. The filed strp_aa should update only if its null with MAX strp_aa + 1, and if its not null if it already has a number it should stay the same.
short version of code is
UPDATE STRANKEP
SET strp_aa = IF(strp_aa=null, strp_aa+1, strp_aa)
WHERE strp_ID=36;
Also tired
UPDATE STRANKEP
SET strp_aa = IF(strp_aa=null, (SELECT MAX(strp_aa)) +1, (SELECT (strp_aa) WHERE strp_ID=36)
WHERE strp_ID=36;
I tried multiple things like this one mentioned here Update MySQL with if condition:
UPDATE STRANKEP
SET strp_aa = CASE WHEN strp_aa = NULL THEN MAX(strp_aa) + 1 ELSE strp_aa END
WHERE strp_ID = 36;
I have also found this mysql query to update field to max(field) + 1 and tried all sorts of combinations with supplied answer and it wont work for me. One of the version is:
UPDATE STRANKEP
SET strp_aa = IF((SELECT strp_aa )!=null,((SELECT selected_value2 FROM (SELECT (strp_aa) AS selected_value2 FROM STRANKEP WHERE strp_ID=36) AS sub_selected_value2)), ((SELECT selected_value FROM (SELECT MAX(strp_aa) AS selected_value FROM STRANKEP) AS sub_selected_value) + 1) )
WHERE strp_ID=36;
This just keep adding one even if there is a number set on strp_aa...
I don't know what else to try.
EDIT:
Had s little problem with #GMB answer because all fields are starting with NULL, so max(strp_aa) gives 0 results in case none of the fields had a number in it.
I solved that with COALESCE statement and posting it here if someone has similar problem.
UPDATE STRANKEP t
CROSS JOIN (select COALESCE(MAX(strp_aa),0) max_strp_aa from STRANKEP) m
set t.strp_aa = m.max_strp_aa + 1
where t.strp_ID = 36 and t.strp_aa is null
You can use the update ... join syntax for this:
update strankep s
cross join (select max(strp_aa) max_strp_aa from strankep) m
set s.strp_aa = m.max_strp_aa + 1
where s.strp_id = 36 and s.strp_aa is null
The cross join brings the max value of strp_aa over the whole table. The where clause eliminate row(s) where strp_aa is not null.
Im looking to update 500+ records in my mysql database so that the fields will be a value combination of an $incremental_value+db_user_first_name+#some_static_text. An example of the wished outcome:
1_firstname#staticstring.com, 2_george#staticstring.com, 3_johnny#staticstring.com etc.
I've been playing around with some approach as the following, but that naturally doesn't work (modified for hopefully better clarification).
UPDATE user
SET email = (($incremental_value+1)+(user.first_name))"#staticstring.com"
WHERE email = "empty#empty.com"
The correct syntax for string concatenation in MySQL is the concat() function:
UPDATE user cross join
(select #i = VALUETOSTART) var
SET email = concat(#i := #i + 1, '_', user.first_name, '#staticstring.com')
WHERE email = 'empty#empty.com';
There are two types of records in my Db such as MS-NW and CS in the same column of table DICIPLINE I want to wrap if its CS (ANY TWO STRING LIKE CS,TE OR THE LIKE) then wrap it to BS(CS) (OR BS(TE) ETC) or if its MS-NW (Or MS-CS, MS-TE and the like) then wrap it to MS(NW) from the column dicipline.
I updated for two strings successfully and following is the query for that kindly let me know how can i do it for values like MS-NW OR MS-CS and convert it to the format like MS(NW) from following query .
UPDATE DEG set DICIPLINE = concat("BS(",DICIPLINE,")") where CHAR_LENGTH(DICIPLINE) = 2
The below query helps you to update your data.
update deg set DISIPLINE = if(length(DISIPLINE)= 2,concat('BC(',DISIPLINE,')')
,concat('MS(',substr(DISIPLINE, 4,4),')'));
See Sqlfiddle demo.
For safety, create a temporary column of same type and perform an update like this:
UPDATE deg
SET dicipline_temp = CASE
WHEN CHAR_LENGTH(dicipline) = 2
THEN CONCAT('BS(', dicipline, ')')
WHEN CHAR_LENGTH(dicipline) = 5 AND SUBSTRING(dicipline, 3, 1) = '-'
THEN CONCAT(REPLACE(dicipline, '-', '('), ')')
END
WHERE CHAR_LENGTH(dicipline) = 2 OR (CHAR_LENGTH(dicipline) = 5 AND SUBSTRING(dicipline, 3, 1) = '-')
If results are acceptable, update the actual column.
Although there are many questions similar to this, such as
"Updating a record from another table", but i could not get this working.
I have a query that selects and updates table sem_stdexamfinresmark. The select subquery returns multiple rows of data whose size may not be equal to the table being updated, but the update is now working.
The query looks like :
update sem_stdexamfinresmark sr,
(select
se.currsession,
str.studentid,
str.classid,
str.subjectid,
str.aggScore*(select gbtp.percentage from gb_termpercentage gbtp where gbtp.termname = se.examtype)/100 as aggPer,
str.aggGrade
from
sem_stdexamtermresr str,
sem_exam se
where
str.examid=se.examid and
se.examtype = 'Second Term' and
se.currsession =1 and classid='8'
) s
set
sr.SecondTermMark = s.aggPer and
sr.SecondTermGrade = s.aggGrade
where
sr.studentid=s.studentid and
sr.subjectid=s.subjectid and
s.currsession = s.currsession and
sr.classid='8';
EDIT:
update sem_stdexamfinresmark
set
sr.SecondTermMark = s.aggPer and
sr.SecondTermGrade = s.aggGrade
from
(select
se.currsession,
str.studentid,
str.classid,
str.subjectid,
str.aggScore*(select gbtp.percentage from gb_termpercentage gbtp where gbtp.termname = se.examtype)/100 as aggPer,
str.aggGrade
from
sem_stdexamtermresr str,
sem_exam se
where
str.examid=se.examid and
se.examtype = 'Second Term' and
se.currsession = 1 and classid='8'
) s
where
sr.studentid=s.studentid and
sr.subjectid=s.subjectid and
s.currsession =1 and
sr.classid='8';
select * from sem_exam;
update sem_exam set currsession =1;
try something that looks more like:
update foo
set col = bar.col
from bar
where ...
This is what happens when one loses sleep :( I just did a silly mistake here and added "and"