INSERT INTO between tables with INNER JOIN - mysql

An earlier data import in CiviCRM placed some member numbers into a custom field (member_number) instead of the more useful (external_id) field.
My (admittedly limited) SQL skills are way too rusty, but what I'm trying to do is:
IF external_id field is empty,
AND the contact_type is "Individual"
THEN copy the data from member_number to external_id for the matching internal id number.
I've tried a few variations of this, with different errors:
INSERT INTO test_table (external_id)
SELECT member_number
FROM member_info
INNER JOIN test_table
ON memberinfo.entity_id=test_table.id
WHERE test_table.external_id IS NULL AND test_table.contact_type = "Individual"
Do I even really need the INNER JOIN on this? And I know the WHERE statement usually refers to the table you're pulling from, not the one you're inserting to, but I can't remember the right way to do this.

update test_table
set external_id =
if(external_id = '' and contact_type = 'Individual', member_number,external_id)

Related

mysql: I want to sum up all the values of credit from table semester and then add to another column total_credit from another table

I have the below code:
UPDATE VIEW
LEFT JOIN sem_view ON (view.semester = sem_view.semester)
SET view.t_credit = SUM(sem_view.credit)
but its not working saying invalid use of group
Data for updating must be perpared previously, in subquery. Updating must use the data which is already aggregated.
Left joining may be errorneous - it will set the value in the destination table to NULL if according data for the semester in interest in sem_view is not present. But if the logic needs this then you may use LEFT JOIN instead of INNER one in the below query.
Totally:
UPDATE `view`
JOIN ( SELECT sem_view.semester, SUM(sem_view.credit) summ
FROM sem_view
GROUP BY sem_view.semester ) data_for_updating
ON `view`.semester = data_for_updating.semester
SET `view`.t_credit = data_for_updating.summ;
PS. The text looks like view is a name of a table to be updated.

return values of table 1 based on single column in table 2

I have 3 tables that I am using and need to make a query to return data from one table based on the value of a single column in the second table.
tbl_user
ID
login
pass
active
mscID
tbl_master
ID
name
training_date
MSCUnit
Active
tbl_msc
mscID
mscName
my current SQL statement:
SELECT
tbl_master.ID,
tbl_master.name,
tbl_master.training_date,
tbl_master.MSCUnit,
tbl_master.active,
tbl_user.mscID
FROM
tbl_master,
tbl_user
WHERE
tbl_master.active = 1 AND tbl_master.MSCUnit = tbl_user.mscID
The values stored in tbl_msc.mscID is a varchar(11) and it contains a string similar to A00 or A19. This is also the Primary key in the table.
The values stored in tbl_user.mscID matches that of tbl_msc.mscID. The values stored in tbl_master.UnitMSC also matches that of tbl_msc.mscID.
My goal is to return all records from tbl_master where the currently logged in user has the same mscID. The problem I am having is the statement returns all records in tbl_master.
I have tried several different join statements and for some reason, I cannot get this to filter correctly.
I am missing something. Any assistance in the SQL statement would be appreciated.
Thanks,
Will
You should be writing this using joins. I don't know how you know who the current user is, but the idea is to join the three tables together:
SELECT m.ID, m.name, m.training_date, m.MSCUnit, m.active,
u.mscID
FROM tbl_master m JOIN
tbl_user u
ON m.MSCUnit = u.mscID JOIN
tbl_msc msc
ON msc.mscID = u.msc_ID
WHERE m.active = 1 AND msc.mscName = ?;
Notice the use of proper, explicit, standard JOIN syntax and table aliases.
Select a.*, b.userid from
table_master a, table_user b where
a.mscunit in (select mscid from
table_user where active=1)
This should point you in the right direction.

MySQL INSERT INTO single column from a SELECT query pulling data from two other tables - throwing #1062 - Duplicate entry '' for key 2 error

I've got one col (state_not_allowed) in TABLE vendor_product where I'm trying to insert values from product_catalog_varchar.value - but only if there's a sku in vendor_product that matches a sku in product_catalog where product_catalog's id equals product_catalog_varchar's id and product_catalog_varchar's attribute id = 523.
I'm basically trying to do the MySQL equivalent of an Excel VLOOPUP. I need the result of the following query:
SELECT product_catalog_varchar.value
FROM product_catalog_varchar
JOIN product_catalog
ON product_catalog.id = product_catalog_varchar.id
JOIN vendor_product
ON vendor_product.sku = product_catalog.sku
AND product_catalog_varchar.attribute_id = 523
To be inserted in to column state_not_allowed, where the sku in vendor_product = the sku in product_catalog.
I've done some research on INSERT INTO, here and on Google in general. Looks like a lot of the instruction out there is on simplier queries so I haven't been able to find a decent model to figure out what to do. I can tell you that this query doesn't work:
INSERT INTO vendor_product(`state_not_allowed`)
SELECT product_catalog_varchar.value
FROM product_catalog_varchar
JOIN product_catalog
ON product_catalog.id = product_catalog_varchar.id
JOIN vendor_product
ON vendor_product.sku = product_catalog.sku
AND product_catalog_varchar.attribute_id = 523
It throws the following error: #1062 - Duplicate entry '' for key 2
And if I got to vendor_product and look, instead of simply inserting values in to state_not_allowed, it's creating a whole new row (with no data). Clearly, I'm misunderstanding in a fundamental sense here. Help me out? Thanks folks.
This query shows the general idea of what you want to do.
insert into table2
(field1)
select distinct field1
from table1
where field1 in
(select field1
from table1
except
select field1
from table2)
The details vary from RDBMS to RDBMS. For example, Oracle uses the keyword minus instead of except. Your MySql documentation will help you with the details.
Note that while it's tempting to simplify this by using "not in" that construct tends to be slow.

subquery in where clause of UPDATE statement

I have the database of ATM card in which there are fields account_no,card_no,is_blocked,is_activated,issue_date
Fields account number and card numbers are not unique as old card will be expired and marked as is_block=Y and another record with same card number ,account number will be inserted into new row with is_blocked=N . Now i need to update is_blocked/is_activated with help of issue_date i.e
UPDATE card_info set is_blocked='Y' where card_no='6396163270002509'
AND opening_date=(SELECT MAX(opening_date) FROM card_info WHERE card_no='6396163270002509')
but is doesn't allow me to do so
it throws following error
1093 - You can't specify target table 'card_info' for update in FROM clause
Try this instead:
UPDATE card_info ci
INNER JOIN
(
SELECT card_no, MAX(opening_date) MaxOpeningDate
FROM card_info
GROUP BY card_no
) cm ON ci.card_no = cm.card_no AND ci.opening_date = cm.MaxOpeningDate
SET ci.is_blocked='Y'
WHERE ci.card_no = '6396163270002509'
That's one of those stupid limitations of the MySQL parser. The usual way to solve this is to use a JOIN query as Mahmoud has shown.
The (at least to me) surprising part is that it really seems a parser problem, not a problem of the engine itself because if you wrap the sub-select into a derived table, this does work:
UPDATE card_info
SET is_blocked='Y'
WHERE card_no = '6396163270002509'
AND opening_date = ( select max_date
from (
SELECT MAX(opening_date) as_max_date
FROM card_info
WHERE card_no='6396163270002509') t
)

MySQL - How can I update a table with values from another table?

I have the task to repair some invalid data in a mysql-database. In one table there are people with a missing date, which should be filled from a second table, if there is a corresponding entry.
TablePeople: ID, MissingDate, ...
TableEvent: ID, people_id, replacementDate, ...
Update TablePeople
set missingdate = (select replacementDate
from TableEvent
where people_id = TablePeople.ID)
where missingdate is null
and (select count(*)
from TableEvent
where people_id = TablePeople.ID) > 0
Certainly doesn't work. Is there any other way with SQL? Or how can I process single rows in mysql to get it done?
We need details about what's not working, but I think you only need to use:
UPDATE TablePeople
SET missingdate = (SELECT MAX(te.replacementDate)
FROM TABLEEVENT te
WHERE te.people_id = TablePeople.id)
WHERE missingdate IS NULL
Notes
MAX is being used to return the latest replacementdate, out of fear of risk that you're getting multiple values from the subquery
If there's no supporting record in TABLEEVENT, it will return null so there's no change