I have two tables joined up together
I need to see if Product Code from table 1 (On the left) matches with the on on the right, based on their barcodes.. I have managed to inner join the barcodes and show only barcodes that match up. Just the prdouct code is the problem now...
Is this what you want?
select t1.*
from table1 t1
where not exists (select 1
from table2 t2
where t2.code = t1.product_code and t2.barcode = t1.barcode
);
This selects rows from table1 with no matches in table2.
Related
I need to join two tables together based on a three-column key stack. The problem is sometimes one of the key columns is translated and mapped differently in another table. I will attempt to example my issue using code:
select t1.TQ
from table1 t1
left join table2 t2 on t1.comp_cd = t2.comp_cd and t1.plcy_frm = t2.plcy_frm
and t1.val_cd = t2.val_cd
The columns "comp_cd" and "plcy_frm" are fine, however the problem is with val_cd. Sometimes the val_cd in table2 does not map correctly to table1 and must go through a third table, table3. Table3 structure is below:
Val_Cd Mapped_Val_Cd
A123 A564
So -> I need to join on Mapped_Val_Cd value when it exists in Table3, but join on Val_Cd from Table2 when Val_Cd does not exist in Table3.
I hope this makes sense - I have tried Case when exists syntax but cannot get that to work.
Assuming there are no duplicates in table3, you can left join it in and then choose the value that you want in the on clause:
select t1.TQ
from table1 t1 left join
table3 t3
on t1.val_cd = t3.val_cd
table2 t2
on t1.comp_cd = t2.comp_cd and
t1.plcy_frm = t2.plcy_frm and
t1.val_cd = coalesce(t3.Mapped_Val_Cd, t2.val_cd);
I am trying to write an SQL query that will return Table1, which has 10 columns. This table consists of a primary key id, 4 foreign key Id columns, and 5 other columns that I want to return but not change. The goal is to do a join to replace the foreign key Ids with their descriptions that are held in other tables.
Here is one attempt with the first FK Id:
Select * from Table1 t1
left join Table2 t2
on t1.BranchId = t2.BranchId;
This left join returns the description from table2, but does not replace it.
Here is another with the first FK Id:
Select t2.BranchName from Table1 t1
left join Table2 t2
on t1.BranchId = t2.BranchId;
This returns the name I want, but does not return table1 fully.
For the sake of an example you could pretend that OtherName3, OtherName4, OtherName5 are in tables Table3, Table4, Table5, respectively.
This may seem trivial for experienced SQL devs, but I am having a hard time figuring out the syntax.
Thanks!
I'm not sure what you mean by replace it.
I think you just need to list out all the columns you want:
Select t1.col1, t1.col2, t1.col3, . . .,
t2.name
from Table1 t1 left join
Table2 t2
on t1.BranchId = t2.BranchId;
I don't know what you mean by 'replace' but you just need to qualify what columns from which table you want. That goes for all tables you are joined to, especially if they have the same column name in multiple tables. I put junk columns in since I don't know your tables but you should get the general idea.
Select t2.BranchName, t1.BranchId, t1.Name, t1.Amount, t2.BranchLocation from Table1 t1
left join Table2 t2
on t1.BranchId = t2.BranchId;
I think this is what you are looking for:
select t1.*, t2.BranchName from Table1 t1
left join Table2 t2
on t1.BranchId = t2.BranchId;
Return Table1 fully (all columns) and only the description (BranchName) from Table2.
If using SQL Server, see all syntax options for the SELECT clause here:
https://msdn.microsoft.com/en-us/library/ms176104.aspx
I have been working on this problem for 3 months now and gave up once or twice. Yes, I am a novice. I created 3 tables with data. Table 1 has a letter and number. Table 2 has a name, letter and number. Table 3 has the end result. I want to compare the T1 and T2. If the name and number in T1 matches a name and number in table 2. I want the result to in T3 to include name, letter and number. This is what I have so far but it is not working.
SELECT * FROM T1 and SELECT * FROM T2
WHEN
TABLE T1(letter) && TABLE T2(letter)
AND
TABLE T1(number) && TABLE T2(letter)
INSERT INTO TABLE T3 (name,letter,number)
What you need is to do an inner join of the first and second tables based on the attributes name and letter.
SELECT T2.name, T2.letter, T2.number
FROM T1
INNER JOIN T2
ON T1.letter=T2.letter AND T1.number=T2.number;
For more details, you can refer http://www.w3schools.com/sql/sql_join.asp
To expand upon Dinesh's answer,
You'll need an inner join for this. Inner joins gives you rows that match the columns in both tables you've specified.
You can then combine it into an insert statement to put it into your T3 table. So this is one complete SQL statement:
INSERT INTO T3
SELECT T2.name, T2.letter, T2.number
FROM T2
INNER JOIN T1
ON T2.letter = T1.letter
AND T2.number = T1.number;
As a side note, there's also left joins and right joins (and heaps more). Think of Left, Inner, Right joins as two circles in a venn diagram.
my first table has about 18K records
so when i
select * from table2 i get about 18k
i'm trying to do a join on it as follows, but i'm getting like 26K back.. what am i doing wrong? i though it's supposed to return all of the "right" aka table2 records plus show me whatever value matches from the first in a separate column...
Select t1.fID , t2.*
FROM table1 t1 right join table2 t2 on t1.fName = t2.f
here is an exmaple of my tables:
table 1:
fID, fName
table 2: id, f, address, etc
i need to get all records from table 2, with an fID column, whenever f=fName
table1 has many rows with a value of fname that matches the same in table2.
Example, say 5k rows table2 have no matching rows in table1, you have a average of 2 rows in table 1 for each of the remaining 13k table2 rows
Because you have also asked for a column for table1, this will happen. You'll note multiple t1.fId values for a given t2.fname. Or NULLs
If t1.fName and t2.f aren't unique identifiers for their tables, you will find that rows from table1 are being joined with multiple rows from table2.
The RIGHT JOIN keyword Return all rows from the right table (table_name2), even if there are no matches in the left table (table_name1).See Right Join
So it looks like you do not have your matching criteria set correctly or you have no matches.
This is possible when some fName values are repeated in Table2 and/or Table 1.
Run these Queries and See:
SELECT fName, COUNT(1) FROM Table2 GROUP BY fName HAVING COUNT(1) > 1
SELECT fName, COUNT(1) FROM Table1 GROUP BY fName HAVING COUNT(1) > 1
I am a little confused as to how to approach this SQL query.
I have two tables (equal number of records), and I would like to return a column with which is the division between the two.
In other words, here is my not-working-correctly query:
SELECT( (SELECT v FROM Table1) / (SELECT DotProduct FROM Table2) );
How would I do this? All I want it a column where each row equals the same row in Table1 divided by the same row in Table2. The resulting table should have the same number of rows, but I am getting something with a lot more rows than the original two tables.
I am at a complete loss. Any advice?
It sounds like you have some kind of key between the two tables. You need an Inner Join:
select t1.v / t2.DotProduct
from Table1 as t1
inner join Table2 as t2
on t1.ForeignKey = t2.PrimaryKey
Should work. Just make sure you watch out for division by zero errors.
You didn't specify the full table structure so I will assume a common ID column to link rows in the tables.
SELECT table1.v/table2.DotProduct
FROM Table1 INNER JOIN Table2
ON (Table1.ID=Table2.ID)
You need to do a JOIN on the tables and divide the columns you want.
SELECT (Table1.v / Table2.DotProduct) FROM Table1 JOIN Table2 ON something
You need to substitue something to tell SQL how to match up the rows:
Something like: Table1.id = Table2.id
In case your fileds are both integers you need to do this to avoid integer math:
select t1.v / (t2.DotProduct*1.00)
from Table1 as t1
inner join Table2 as t2
on t1.ForeignKey = t2.PrimaryKey
If you have multiple values in table2 relating to values in table1 you need to specify which to use -here I chose the largest one.
select t1.v / (max(t2.DotProduct)*1.00)
from Table1 as t1
inner join Table2 as t2
on t1.ForeignKey = t2.PrimaryKey
Group By t1.v