Suppose I have 2 tables
Table1
ID Path
-- ----
1 PathA
2 PathB
3 PathC
4 PathD
Table2
ID Path Table1ID
-- ---- --------
23 PathA 1
24 PathX 2
25 PathC 3
26 PathZ 4
In the above, PathX should be PathB and PathZ should be PathD
How do I sync all the path values in Table2 with values in Table 1, the tables could be large so would like to check for all values that do not match and update them.
Cheers
Using MS SQL Server 2005
The following is I believe the simplest:
UPDATE TableB SET Path = TableA.Path
FROM TableA
WHERE TableB.Id = TableA.ID AND TableB.Path <> TableA.Path
I suppose this should do the trick...
UPDATE Table2 SET
Path = t1.Path
FROM Table2 t2
INNER JOIN Table1 t1 ON
t1.ID = t2.Table2ID
WHERE
t1.Path != t2.Path;
Edit: Sorry I believe I misinterpreted your request. I thought you wanted Table2 values into Table1. I've changed it to be the other way around.
If i am understanding your question correctly this will update the paths on table2 with values from table1
Update Table2
set path = b.path
From Table2 a
Left outer join Table1 b
on a.Table1ID = b.ID
Where ltrim(rtrim(a.Path)) <> ltrim(rtrim(b.Path))
Your example demonstrates how you can (will) get anomalies if you do not normalize your tables.
In Table2 either store Table1ID or Path but not both, you can query for the other (perhaps recreate your current Table2 as a VIEW. Whichever column you choose for Table2, ensure you have a foreign key on it referencing Table1.
The best way
UPDATE TableB SET Path = TableA.Path
FROM TableA
WHERE TableB.Id = TableA.ID AND TableB.Path <> TableA.Path
Related
I am trying to find the "users" that are missing a value in a 2nd table with the value of column "A" = 16 and then column "B" = 0.
I am looking for these values because that would give me the ability to run a query adding a row for each user that is missing the row with the values of A = 16 and B = 0.
So here is the relevant structure of the tables that we would be joining on.
There are two tables, table 1 and table 2
Table 1
ID
parent id
table 2
table1_id
A
B
The problem I am running into is that table2 can have records associated with the table1_id but still needing to verify if the table2 if there is not a row with table1_id, A missing value 16 while B is missing value 0.
Here is the current idea I am working off of for the sql query
SELECT
*
FROM
table1
LEFT JOIN
table2 ON table1.id = table2.table1_id
WHERE
table1.id IS NOT NULL
AND table2.id IS NULL;
This will give me all the table1_ids that are missing records from table2 but does however would not pull the rows where there are rows for the table1_id but however does not determine if there are missing rows with the column A with value 16 or Column B = 0.
If you are able to answer that would be greatly appreciated. I just currently cannot think of a way I can logically create a query that would do this.
So, you want all rows from table 1
And you want rows from table 2 that are A=16, B=0
And you want to know where the relationship breaks down between table1 and table2:
SELECT t1.*
FROM
table1 t1
LEFT JOIN
(
SELECT * FROM table2 WHERE A=16 and B=0
) a16b0
ON
t1.id = a16b0.table1_id
WHERE
a16b0.table1_id IS NULL
There are more ways to skin this cat, but this should be fairly understandable in the sense of "join table1 to (just the a16/b0 rows from table2)"
Another form you might get on with uses EXISTS:
SELECT * FROM table1 t1
WHERE NOT EXISTS(
SELECT null FROM table2 t2
WHERE t2.table1_id = t1.id AND t2.A = 16 AND t2.B = 0
)
In english it's "Select all from table 1 where, for any particular t1 row, there does not exist a t2 row that has: a matching id in table1_id, a 16 in a, a 0 in b"
A slightly less popular form (historical performance reasons probably) would be perhaps:
SELECT * FROM table1 t1
WHERE id NOT IN (
SELECT table1_id FROM table2 WHERE A = 16 AND B = 0
)
"select everything from table1 where the row's id is not in the list of IDs that are a16/b0 from table 2" - in essence this forms a "big list of everything we dont want" and then says "get me everything that isn't in the list of don't-wants"
This is the solution.
SELECT
*
FROM
table1
LEFT JOIN
table1.id = table2.table1_id AND table2.A = 16 AND table2.B = 0
WHERE
table2.id IS NULL;
#jon Armstrong, thanks for the help.
This is a simplified version of a problem I have. Say I’ve got three variables all of the same type, in three columns of table1, and an id field. They are all codes. Mostly they map to variables (group identifyers say) contained in a look up in table2. I want to write a query that does the following:
For each of my records I want to return the variable in table2 that my matches the code in the first of the three columns in table1. However, if the variable in this column contains a value that does not have a match in table2, I want to try for a match using column2. If that one does not match, use the one in column3.
I want the query result to contain the ID from table1 and the match from table2. If there is no match at all, then I want the query to contain a row with the id and n/a.
In this example there are just two values that match in my lookup. I'm actually mapping across 12 columns with a few hundreds of unique code values and several million rows of data.
Table1
id col1 col2 col3
1 V21 G22 T21
2 E30 W21 S34
3 Y11 U29 Q66
Table2
cat_code class_group
V21 group1
W21 group2
Query result
id class_group
1 group1
2 group2
3 n/a
So here in the desired result the record id 1 gets to match the very first column, and returns the corresponding variable, the second record can't get a match on the first but finds one on the second column and the third records can't match any value in any of the three columns so it throws an n/a.
I'm fairly new to SQL - I'm not sure whether this can be achieved in a simple query or whether it needs a functon.
select t1.id,
coalesce(t21.class_group, t22.class_group, t23.class_group) class_group
from Table1 t1
left join Table2 t21 on t21.cat_code = t1.col1
left join Table2 t22 on t22.cat_code = t1.col2
left join Table2 t23 on t23.cat_code = t1.col3
Just like Joel wrote... but he's quicker than I am :)
SELECT [Id], COALESCE(C1.[class_group], C2.[class_group], C2.[class_group], 'N/A')
FROM Table1 AS T1
LEFT JOIN Table2 AS C1 ON C1.[cat_code] = T1.[col1]
LEFT JOIN Table2 AS C2 ON C2.[cat_code] = T1.[col2]
LEFT JOIN Table2 AS C3 ON C3.[cat_code] = T1.[col3]
http://sqlfiddle.com/#!6/ffb01/3
Try this sql query:
SELECT table1.id, table2.class_group
FROM table1
INNER JOIN table2 ON table1.col1 = table2.cat_code
UNION
SELECT table1.id, table2.class_group
FROM table1
INNER JOIN table2 ON table1.col2 = table2.cat_code
SELECT table1.id, table2.class_group
FROM table1
INNER JOIN table2 ON table1.col3 = table2.cat_code
I have been searching for this scenario that has come across my desk, I have been searching reference sites but haven't had luck creating the correct SQL statement to complete this task.
Here is the PSEUDO code for the scenario.
UPDATE TABLE1
SET TABLE1.ID = TABLE1.From_ID,
TABLE1.VALUE = 'ALL'
WHERE TABLE1.From_ID = TABLE2.ID
AND TABLE2.NAME = 'TEST'
Basically I need to update two columns in TABLE1 only if the id from TABLE1 matches the ID's in the TABLE2 and the description column in TABLE2 equals to a string value the caveat is that TABL1 columns can't be change only if there is a correlation between the ID's from TABLE1 and TABLE2 and in TABLE2 that ID correlates to description column for a specific string value. Below is table structure and end result I'm trying to get too.
TABLE1:
FIELD_ID CONDITIONAL_VALUE FROM_FIELDID
--------------------------------------------
1 TEST 3
7 TEST 4
5 ANY 7
TABLE2:
FIELD_ID Description
----------------------------------------------
3 BLUE
4 BLUE
7 RED
In Transact-SQL (SQL Server's dialect of SQL), you need a FROM clause in your SQL if you specify more than the table you're trying to update.
update
TABLE1.ID
set
TABLE1.ID = TABLE1.From_ID ,
TABLE1.VALUE = 'ALL'
from
TABLE1,
TABLE2
where
TABLE1.From_ID = TABLE2.ID
AND TABLE2.NAME = ''TEST
You need to join data from TABLE1 to TABLE2
UPDATE t1
SET t1.ID = t1.From_ID
,t1.VALUE = 'ALL'
FROM Table1 AS t1
JOIN table2 AS t2
ON t1.From_ID = t2.ID
AND t2.NAME = 'TEST't1
I need to copy ref_id1 from table1 TO the column ref_id2 in the table2 the two things matching will be : id (same column name), a_ref1 & b_ref1 (column names are different but numerical value will be identical).
Table1
ID ref_id1 a_ref1
9 2.3456762498; 1367602349
9 1.61680784158; 1367653785
9 2.63461385408; 1367687746
9 0; 1367688520
9 0.780442217152; 1367740313
9 3.18328461662; 1367773889
9 0.775471247616; 1367774978
Table2
ID b_ref1 ref_id2
9 1367602349;
9 1367740313;
9 1367774978;
2 1357110511;
2 1357186899;
2 1357195928;
2 1357199525;
In a nutshell need to copy ref_id1 to ref_id2 by comparing id and a_ref1 with b_ref1, Please let me know how to do that.
UPDATE public.clean_trips_byobu
SET trip_dist = clean_trips.bktp_mt_total
FROM public.clean_trips
WHERE public.clean_trips.obu_id = clean_trips_byobu.obu_id
AND clean_trips.bktp_trip_id = clean_trips_byobu.trip_id;
Hope it will work for you.
UPDATE Table2 --format schema.table_name
SET
ref_id2 = table1.ref_id1
FROM table1 -- mention schema name
WHERE table1.id = table2.id
AND
table1.a_ref1 = table2.b_ref1;
What you want is
UPDATE Table2
SET ref_id2 = table1.ref_id1
FROM table1
WHERE table1.id = table2.id
AND table1.a_ref1 = table2.b_ref1;
Edit This is what you actually want
As seen here (crudely)
I think this should work:
UPDATE Table2
SET ref_id2 = ref_id1
FROM Table2
JOIN Table1 ON
Table2.Id = Table1.Id AND Table2.a_ref1 = Table1.b_ref1
I need to write an SQL script that selects one record in table1, then does a lookup in the remaining tables in the database. If it doesn't find the record, I need delete the record from table1. Anyone provide some sample script?
One example
delete table1
where not exists (select 1
from Table2
where table1.SomeColumn = Table2.SomeColumn)
AND table1.SomeColumn = 5 --just an example,
Leave the AND out if you want to delete all the rows from table 1 that do not exist in table 2
you can also use LEFT JOIN or NOT IN
I have done things like this:
DELETE table1
FROM table1
WHERE table1.ID NOT IN (
SELECT RefID FROM Table2
UNION
SELECT RefID FROM Table3
...
)
Assuming RefID are FK's to table1.ID. Is this what you need?
DELETE FROM Table1 WHERE id=10 AND NOT EXISTS (SELECT * FROM Table2 WHERE id=10);
Very generally, (since you gave little details)
Delete Table1 t1
Where [Criteria to find table1 Record]
And Not Exists(Select * From Table2
Where pk = t1.Pk)
And Not Exists(Select * From Table3
Where pk = t1.Pk)
And Not Exists(Select * From Table4
Where pk = t1.Pk)
... etc. for all other tables