I have two tables, playgrounds and maintenance, which are linked with a foreign key. Whenever there is a maintenance on a playground, it will be saved in the table and connected to the respective playground.
Table A (playgrounds):
playground_number
Table B (maintenance):
playground_number (foreign key),
maintenance_type (3 different types),
date
What I now want is to retrieve all the playgrounds on which a certain type of maintenance has NOT been performed yet IN a certain year. For instance all playgrounds that do not have a maintenance_type = 1 in the year 2022 connected yet, although there could be multiple other maintenance_types because they are more frequent.
This is what I have tried (pseudo):
SELECT DISTINCT A.playground_number
FROM table A
JOIN table B ON A.playground_number = B.playground_number (FK)
WHERE NOT EXISTS (SELECT B.maintenance_type FROM table B
WHERE B.maintenance_type = 1 AND year(B.date) = 2022
However this will return nothing as soon as there is only one entry with maintenance_type 1 within the table.
I am struggling with this query for a while, so would appreciate some thoughts :) Many thanks.
You need to correlate the exists subquery to the outer B table. Also, you don't even need the join.
SELECT DISTINCT a.playground_number
FROM table_a a
WHERE NOT EXISTS (
SELECT 1
FROM table_b b
WHERE b.playground_number = a.playground_number AND
b.maintenance_type = 1 AND
YEAR(b.date) = 2022
);
Please consider this. I don't think you need JOIN.
SELECT DISTINCT A.playground_number
FROM table A
WHERE A.playground_number NOT IN (SELECT B.playground_number FROM table B
WHERE B.maintenance_type = 1 AND year(B.date) = 2022)
Please let me know if I understand it incorrectly.
Related
There are two tables Table A and Table B. These contains the same columns cost and item. The Table B contains the list of items and their corresponding costs whereas the Table A contains only the list of items.
Now we need to check the items of Table A, if they are present in the Table B then the corresponging item cost should be assigned to the item's cost in Table A.
Can someone help me out by writing a query for this.
Consider the tables as shown:
Table A:
item cost
-------------
pen null
book null
watch null
Table B:
item cost
-------------
watch 1000
book 50
Expected output
Table A:
item cost
pen 0
book 50
watch 1000
Just add a foreign key (primary key of table A) in the Table B as you can say table A ID then add a join(right join may be) in the query to get or assign the prices respective items.
join be like
SELECT item, cost
FROM tablename a
RIGHT JOIN tablename b ON a.item= b.item;
Edit:
Just edit this table name ,now run it.
I would structure the update like this:
with cost_data as (
select
item,
max (cost) filter (where item = 'watch') as watch,
max (cost) filter (where item = 'book') as book
from table_b
group by item
)
update table_a a
set
watch = c.watch,
book = c.book
from cost_data c
where
a.item = c.item and
(a.watch is distinct from c.watch or
a.book is distinct from c.book)
In essence, I am doing a common table expression to do a poor man's pivot table on the Table B to get the rows into columns. One caveat here -- if there are multiple costs listed for the same item, this may not do what you want, but then you would need to know how to handle that in almost any case.
Then I am doing an "update A from B" against the CTE.
The last part is not critical, per se, but it is helpful -- to limit the query to only execute on rows that need to change. It's best to limit DML if it doesn't need to occur (the best way to optimize something is to not do it).
There are plenty of ways you could do this, if you are taking table b to be the one containing the price then a left outer join would do the trick.
SELECT
table_a.item,
CASE
WHEN table_b.cost IS NULL
THEN 0
ELSE table_b.cost
END as cost
FROM table_a
LEFT OUTER JOIN table_b ON table_a.item = table_b.item
The result also appears to suggest that pen which is not in table b should have a price of 0 (this is bad practice) but for the sake of returning the desired result you will want a case statement to assign a value if it is null.
In order to update the table, as per the comment
update table_a set cost = some_alias.cost
from (
SELECT
table_a.item,
CASE
WHEN table_b.cost IS NULL
THEN 0
ELSE table_b.cost
END as cost
FROM table_a
LEFT OUTER JOIN table_b ON table_a.item = table_b.item
) some_alias
where table_a.item = some_alias.item
I have two tables. A and B.
Table Structure:
A (A_ID, A_AMT, A_QTY)
B (B_ID, B_AMT, B_QTY)
I need to find IDs not with the same AMT and QTY values.
For example: If A_AMT is 5 and B_AMT is 10 then I need to find the difference between them as 5 and return them.
Can someone help me with this.
Note: Both the tables have the same IDs. A_ID = B_ID.
Try this:
SELECT A.A_AMT,
B.B_AMT,
A.A_AMT - B.B_AMT AS DIFF_AMT,
A.A_QTY,
B.B_QTY,
A.A_QTY - B.B_QTY AS DIFF_QTY
FROM A INNER JOIN
B ON A.A_ID = B.B_ID
WHERE A.A_AMT <> B.B_AMT OR A.A_QTY <> B.B_QTY
I have a master table in sql server 2012 that consists of two types.
These are the critical columns I have in my master table:
TYPE CATEGORYGROUP CREDITORNAME DEBITORNAME
One of those two types (Type B) doesn't have a CategoryGroup assigned to it (so it's always null).
Type A always has a CategoryGroup and Debitor.
Type B always has a Creditor but no CategoryGroup.
For creditor and debitor I have two extra tables that also hold the CategoryGroup but for my task I only need the table for creditors since I already have the right value for type A (debitors).
So my goal is to look-up the CategoryGroup in the creditor table based on the creditor name and ideally put those CategoryGroup values in my master table.
With "put" I'm not sure if a view should be generated or actually put the data in the table which contains about 1.5 million records and keeps on growing.
There's also a "cluster table" that uses the CategoryGroup as a key field. But this isn't part of my problem here.
Please have a look at my sample fiddle
Hope you can help me.
Thank you.
If I understand you correctly, you can simply do a join to find the correct value, and update MainData with that value;
You can either use a common table expression...
WITH cte AS (
SELECT a.*, b.categorygroup cg
FROM MainData a
JOIN CreditorList b
ON a.creditorname = b.creditorname
)
UPDATE cte SET categorygroup=cg;
An SQLfiddle to test with.
...or an UPDATE/JOIN;
UPDATE m
SET m.categorygroup = c.categorygroup
FROM maindata m
JOIN creditorlist c
ON m.creditorname = c.creditorname;
Another SQLfiddle.
...and always remember to test before running potentially destructive SQL from random people on the Internet on your production data.
EDIT: To just see the date in the same format without doing the update, you can use;
SELECT
a.type, COALESCE(a.categorygroup, b.categorygroup) categorygroup,
a.creditorname, a.debitorname
FROM MainData a
LEFT JOIN CreditorList b
ON a.creditorname = b.creditorname
Yet another SQLfiddle.
Couldn't you just do:
update maindata
set categorygroup = (
select top 1 categorygroup
from creditorlist
where creditorname = maindata.creditorname)
where creditorname is not null
and categorygroup is null
?
Try this -
update m
set m.CategoryGroup = cl.CategoryGroup
-- select m.creditorName,
-- m.CategoryGroup as Dest,
-- cl.CategoryGroup as Src
from maindata as m
left join creditorlist as cl
on m.creditorName = cl.creditorName
where m.creditorName is not null
Before you update, you can check the results of the query by uncommenting the update statement and removing the updates.
I have a single table of activities, some labelled 'Assessment' (type_id of 50) and some 'Counselling' (type_id of 9) with dates of the activities. I need to compare these dates to find how long people wait for counselling after assessment. The table contains rows for many people, and that is the primary key of 'id'. My problem is how to produce a result row with both the assessment details and the counselling details for the same person, so that I can compare the dates. I've tried joining the table to itself, and tried nested subqueries, I just can't fathom it. I'm using Access 2010 btw.
Please forgive my stupidity, but here's an example of joining the table to itself that doesn't work, producing nothing (not surprising):
Table looks like:
ID TYPE_ID ACTIVITY_DATE_TIME
----------------------------------
1 9 20130411
1 v 50 v 20130511
2 9 20130511
3 9 20130511
In the above the last two rows have only had assessment so I want to ignore them, and just work on the situation where there's both assessment and counselling 'type-id'
SELECT
civicrm_activity.id, civicrm_activity.type_id,
civicrm_activity.activity_date_time,
civicrm_activity_1.type_id,
civicrm_activity_1.activity_date_time
FROM
civicrm_activity INNER JOIN civicrm_activity AS civicrm_activity_1
ON civicrm_activity.id = civicrm_activity_1.id
WHERE
civicrm_activity.type_id=9
AND civicrm_activity_1.type_id=50;
I'm actually wondering whether this is in fact not possible to do with SQL? I hope it is possible? Thank you for your patience!
Sounds to me like you only want to get the ID numbers where you have a TYPE_ID entry of both 9 and 50.
SELECT DISTINCT id FROM civicrm_activity WHERE type_id = '9' AND id IN (SELECT id FROM civicrm_activity WHERE type_id = '50');
This will give you a list of id's that has entries with both type_id 9 and 50. With that list you can now go and get the specifics.
Use this SQL for the time of type_id 9
SELECT activity_date_time FROM civicrm_activity WHERE id = 'id_from_last_sql' AND type_id = '9'
Use this SQL for the time of type_id 50
SELECT activity_date_time FROM civicrm_activity WHERE id = 'id_from_last_sql' AND type_id = '50'
Your query looks OK to me, too. The one problem might be that you use only one table alias. I don't know, but perhaps Access treats the table name "specially" such that, in effect, the WHERE clause says
WHERE
civicrm_activity.type_id=9
AND civicrm_activity.type_id=50;
That would certainly explain zero rows returned!
To fix that, use an alias for each table. I suggest shorter ones,
SELECT A.id, A.type_id, A.activity_date_time,
B.type_id, B.activity_date_time
FROM civicrm_activity as A
JOIN civicrm_activity as B
ON A.id = B.id
WHERE A.type_id=9
AND B.type_id=50;
Currently struggling with finding a way to validate 2 tables (efficiently lots of rows for Table A)
I have two tables
Table A
ID
A
B
C
Table matched
ID Number
A 1
A 2
A 9
B 1
B 9
C 2
I am trying to write a SQL Server query that basically checks to make sure for every value in Table A there exists a row for a variable set of values ( 1, 2,9)
The example above is incorrect because t should have for every record in A a corresponding record in Table matched for each value (1,2,9). The end goal is:
Table matched
ID Number
A 1
A 2
A 9
B 1
B 2
B 9
C 1
C 2
C 9
I know its confusing, but in general for every X in ( some set ) there should be a corresponding record in Table matched. I have obviously simplified things.
Please let me know if you all need clarification.
Use:
SELECT a.id
FROM TABLE_A a
JOIN TABLE_B b ON b.id = a.id
WHERE b.number IN (1, 2, 9)
GROUP BY a.id
HAVING COUNT(DISTINCT b.number) = 3
The DISTINCT in the COUNT ensures that duplicates (IE: A having two records in TABLE_B with the value "2") from being falsely considered a correct record. It can be omitted if the number column either has a unique or primary key constraint on it.
The HAVING COUNT(...) must equal the number of values provided in the IN clause.
Create a temp table of values you want. You can do this dynamically if the values 1, 2 and 9 are in some table you can query from.
Then, SELECT FROM tempTable WHERE NOT IN (SELECT * FROM TableMatched)
I had this situation one time. My solution was as follows.
In addition to TableA and TableMatched, there was a table that defined the rows that should exist in TableMatched for each row in TableA. Let’s call it TableMatchedDomain.
The application then accessed TableMatched through a view that controlled the returned rows, like this:
create view TableMatchedView
select a.ID,
d.Number,
m.OtherValues
from TableA a
join TableMatchedDomain d
left join TableMatched m on m.ID = a.ID and m.Number = d.Number
This way, the rows returned were always correct. If there were missing rows from TableMatched, then the Numbers were still returned but with OtherValues as null. If there were extra values in TableMatched, then they were not returned at all, as though they didn't exist. By changing the rows in TableMatchedDomain, this behavior could be controlled very easily. If a value were removed TableMatchedDomain, then it would disappear from the view. If it were added back again in the future, then the corresponding OtherValues would appear again as they were before.
The reason I designed it this way was that I felt that establishing an invarient on the row configuration in TableMatched was too brittle and, even worse, introduced redundancy. So I removed the restriction from groups of rows (in TableMatched) and instead made the entire contents of another table (TableMatchedDomain) define the correct form of the data.