I have 5 different tables T_DONOR, T_RECIPIENT_1, T_RECIPIENT_2, T_RECIPIENT_3, and T_RECIPIENT_4. All 5 tables have the same CONTACT_ID.
This is the T_DONOR table:
T_RECIPIENT_1:
T_RECIPIENT_2:
This is what I want the final table to look like with more recipients and their information to the right.
T_RECIPIENT_3 and T_RECIPIENT_4 are the same as T_RECIPIENT_1 and T_RECIPIENT_2 except that they have different RECIPIENT ID and different names. I want to combine all 5 of these tables so on one line I can have the DONOR_CONTACT_ID which his information, and then all of the Recipient's information.
The problem is that when I try to run a query, it does not work because not all of the Donors have all of the recipient fields filled, so the query will run and give a blank table. Some instances I have a Donor with 4 Recipients and other times I have a Donor with only 1 Recipient so this causes a problem. I've tried running queries where I connect them with the DONOR_CONTACT_ID but this will only work if all of the RECIPIENT fields are filled. Any suggestions on what to do? Is there a way I could manipulate this in VBA? I only know some VBA, I'm not an expert.
First I think you want all rows from T_DONOR. And then you want to pull in information from the recipient tables when they include DONOR_CONTACT_ID matches. If that is correct, LEFT JOIN T_DONOR to the other tables.
Start with a simpler set of fields; you can add in the "name" fields after you get the joins set to correctly return the rest of the data you need.
SELECT
d.DONOR_CONTACT_ID,
r1.RECIPIENT_1,
r2.RECIPIENT_1
FROM
(T_DONOR AS d
LEFT JOIN T_RECIPIENT_1 AS r1
ON d.ORDER_NUMBER = r1.ORDER_NUMBER)
LEFT JOIN T_RECIPIENT_2 AS r2
ON d.ORDER_NUMBER = r2.ORDER_NUMBER;
Notice the parentheses in the FROM clause. The db engine requires them for any query which includes more than one join. If possible, set up your joins in Design View of the query designer. The query designer knows how to add parentheses to keep the db engine happy.
Here is a version without aliased table names in case it's easier to understand and set up in the query designer ...
SELECT
T_DONOR.DONOR_CONTACT_ID,
T_RECIPIENT_1.RECIPIENT_1,
T_RECIPIENT_2.RECIPIENT_1
FROM
(T_DONOR
LEFT JOIN T_RECIPIENT_1
ON T_DONOR.ORDER_NUMBER = T_RECIPIENT_1.ORDER_NUMBER)
LEFT JOIN T_RECIPIENT_2
ON T_DONOR.ORDER_NUMBER = T_RECIPIENT_2.ORDER_NUMBER;
SELECT T_DONOR.ORDER_NUMBER, T_DONOR.DONOR_CONTACT_ID, T_DONOR.FIRST_NAME, T_DONOR.LAST_NAME, T_RECIPIENT_1.RECIPIENT_1, T_RECIPIENT_1.FIRST_NAME, T_RECIPIENT_1.LASTNAME
FROM T_DONOR
JOIN T_RECIPIENT_1
ON T_DONOR.DONOR_CONTACT_ID = T_RECIPIENT_1.DONOR_CONTACT_ID
This shows you how to JOIN the first recipient table, you should be able to follow the same structure for the other three...
Related
Could someone please tell explain to me how to properly process a query that collects information from 2 tables, i thought I had this figured out until I added more records. Please look at the image I have below:enter image description here
(The last record should not have the name "Thomas Murray" in it)
Then there is the query I am processing:
"select a.*, b.forenames, b.surname FROM playerSkills a, playerdb b GROUP BY sheetNo"
What I was hoping to do is collect all from the playerSkills database (which it does) and only bring over the names from the second database (playerdb) that matched with the playerID but as I want to return more than one result so I don't know what to do as it returns the whole column and just pastes the one name into every field.
Though I am sure a JOIN is to be inserted here, I am not sure which or at all.
I am not experienced with SQL but trying to wrap my head around it. I have experimented with the JOIN clauses but didn't get far probably due to a syntax.
How can join the names to the playerID so they appear in the appropriate fields?
You need columns to join on . . . and proper join syntax:
select ps.*, p.forenames, p.surname
FROM playerSkills ps JOIN
playerdb p
ON ps.playerId = p.playerId;
Notes:
Your query does not require GROUP BY.
Your query does require JOIN conditions.
Kudos for using table aliases. They should be abbreviations for the table name.
You want to always use explicit JOIN syntax. No commas in the FROM clause.
I have two DB tables each containing email addresses
One is mssql with 1.500.000.000 entries
One is mysql with 70.000.000 entries
I now want to check how many identical email addresses are present in both tables.
i.e. the same address is present in both tables.
Which approach would be the fastest:
1. Download both datasets as csv, load it into memory and compare in program code
2. Use the DB queries to get the overlapping resultset.
if 2 is better: What would be a suggested SQL query?
I would go with a DBQuery. Set up a linked server connection between the two DBs (probably on the MSSQL side), and use a simple inner join query to produce the list of e-mails that occur in both tables:
select a.emailAddress
from MSDBServ.DB.dbo.Table1 a
join MySqlServ.DB..Table2 b
on a.EmailAddress = b.EmailAddress
Finding the set difference, that's going to take more processor power (and it's going to produce at least 1.4b results in the best-case scenario of every MySql row matching an MSSQL row), but the query isn't actually that much different. You still want a join, but now you want that join to return all records from both tables whether they could be joined or not, and then you specifically want the results that aren't joined (in which case one side's field will be null):
select a.EmailAddress, b.EmailAddress
from MSDBServ.DB.dbo.Table1 a
full join MySqlServ.DB..Table2 b
on a.EmailAddress = b.EmailAddress
where a.EmailAddress IS NULL OR b.EmailAddress IS NULL
You could do a sql query to check how many identical email addresses are present in two databases: first number is how many duplicates, second value is the email address.
SELECT COUNT(emailAddr),emailAddr FROM table1 A
INNER JOIN
table2 B
ON A.emailAddr = B.emailAddr
Table1 has the 70,000,000 email addresses, table2 has the 1,500,000,000. I use Oracle so the Upper function may or may not have an equivalent in MySQL.
Select EmailAddress from table1 where Upper(emailaddress) in (select Upper(emailaddress) from table2)
Quicker than comparing spreadsheets and this assumes both tables are in the same database.
I'm currently having a problem with a legacy app I just inherited on my new job. I have a SQL query that's way too long to respond and I need to find a way to fasten it.
This query acts on 3 tables:
SESSION contains all users visits
CONTACT contains all the messages people have been sending through a form and contains a "session_id" field that links back to the SESSION id field
ACCOUNT contains users accounts (people who registered on the website) and whose "id" field is linked back in SESSION (through a "SESSION.account_id" field). ACCOUNT and CONTACT are no linked in any way, besides the SESSION table (legacy app...).
I can't change this structure unfortunately.
My query tries to recover ALL the interesting sessions to serve to the administrator. I need to find all sessions that links back to an account OR a contact form.
Currently, the query is structured like that :
SELECT s.id
/* a few fields from ACCOUNT and CONTACT tables */
FROM session s
LEFT JOIN account act ON act.id = s.account_id
LEFT JOIN contact c on c.session_id = s.id
WHERE s.programme_id = :program_id
AND (
c.id IS NOT NULL
OR
act.id IS NOT NULL
)
Problem is, the SESSION table is growing pretty fast (as you can expect) and with 400k records it slows things down for some programs ( :programme_id in the query).
I tried to use an UNION query with two INNER JOIN query, one between SESSION and ACCOUNT and the other one between SESSION and CONTACT, but it doesn't give me the same number of records and I don't really understand why.
Can somebody help me to find a better way to make this query ?
Thanks a lot in advance.
I think you just need indexes. For this query:
SELECT s.id
/* a few fields from ACCOUNT and CONTACT tables */
FROM session s LEFT JOIN
account act
ON act.id = s.account_id LEFT JOIN
contact c
ON c.session_id = s.id
WHERE s.programme_id = :program_id AND
(c.id IS NOT NULL OR act.id IS NOT NULL);
You want indexes on session(programme_id, account_id, id), account(id) and contact(session_id).
It is important that programme_id be the first column in the index on session.
#Gordon already suggested you add an index, which is generally the easy and effective solution, so I'm going to answer a different part of your question.
I tried to use an UNION query with two INNER JOIN query, one between
SESSION and ACCOUNT and the other one between SESSION and CONTACT, but
it doesn't give me the same number of records and I don't really
understand why.
That part is rather simple: the JOIN returns a result set that contains the rows of both tables joined together. So in the first case you would end up with a result that looks like
session.id, session.column2, session.column3, ..., account.id, account.column2, account.column3, ....
and a second where
session.id, session.column2, session.column3, ..., contact.id, contact.column2, contact.column3, ....
Then an UNION will faill unless the contact and account tables have the same number of columns with correspoding types, which is unlikely. Otherwise, the database will be unable to perform a UNION. From the docs (emphasis mine):
The column names from the first SELECT statement are used as the column names for the results returned. Selected columns listed in corresponding positions of each SELECT statement should have the same data type. (For example, the first column selected by the first statement should have the same type as the first column selected by the other statements.)
Just perform both INNER JOINs seperately and compare the results if you're unsure.
If you want to stick to an UNION solution, make sure to perform a SELECT only on corresponding columns : doing SELECT s.id would be trivial but it should work, for instance.
I am working in mysql with queries, but I am new to this. I am joining 5 tables where each table has an identifier and one table is the master. Each related table may have more than one associated record to the master table. I am attempting to join these tables but I can't seem to get rid of the duplicated data.
I want all of the related records to be displayed, but I don't want the data in the master table to display for all results in the related tables. I have tried so many different methods but nothing has worked. Currently I have 4 queries that work for the separate tables, but I have not successfully joined them to have the results display the multiple records in the related table but just one record from the master table.
Here are my individual queries that work:
SELECT
GovernmaxAdditionsExtract.AdditionDescr,
GovernmaxAdditionsExtract.BaseArea,
GovernmaxAdditionsExtract.Value
FROM
GovernmaxExtract
INNER JOIN GovernmaxAdditionsExtract
ON GovernmaxExtract.mpropertyNumber = GovernmaxAdditionsExtract.PropertyNumber
WHERE (((GovernmaxExtract.mpropertyNumber)="xxx-xxx-xx-xxx"));
SELECT
GovernmaxExtract.mpropertyNumber,
GovernmaxDwellingExtract.CardNumber,
GovernmaxDwellingExtract.MainBuildingType,
GovernmaxDwellingExtract.BaseArea
FROM
GovernmaxExtract INNER JOIN
GovernmaxDwellingExtract ON GovernmaxExtract.mpropertyNumber = GovernmaxDwellingExtract.PropertyNumber
WHERE (((GovernmaxExtract.mpropertyNumber)="xxx-xxx-xx-xxx"));
Using these sub queries, I tried to put together 2 of the tables, but now I am getting all records back and it is not reading my input parameter:
SELECT GE.mpropertynumber
FROM
GovernmaxExtract AS GE,
(SELECT
GovernmaxAdditionsExtract.AdditionDescr,
GovernmaxAdditionsExtract.BaseArea,
GovernmaxAdditionsExtract.Value
FROM GovernmaxExtract INNER JOIN
GovernmaxAdditionsExtract ON
governmaxextract.mpropertyNumber = GovernmaxAdditionsExtract.PropertyNumber) AS AE
WHERE GE.mpropertynumber = 'xxx-xxx-xx-xxx'
I tried nested queries, lots of different joins, and I am just not able to wrap my head around this. I am pretty sure I want to do a nested query since I want the main data from the Governmax table to display once with the main data and all records with all info for the associated tables. Maybe I am going about it all wrong.
Our original code was:
SELECT
ge.*,
gde.*,
gfe.*,
gae.*,
goie.*
FROM governmaxextract AS ge
LEFT JOIN governmaxdwellingextract AS gde
ON ge.mpropertyNumber = gde.PropertyNumber
LEFT JOIN governmaxfeaturesextract AS gfe
ON gde.PropertyNumber = gfe.PropertyNumber
LEFT JOIN governmaxadditionsextract AS gae
ON gde.PropertyNumber = gae.PropertyNumber
RIGHT JOIN governmaxotherimprovementsextract AS goie
ON gde.PropertyNumber = goie.PropertyNumber
WHERE ge.mpropertyNumber = '$codeword'
ORDER BY goie.CardNumber
But this gives multiple rows from the master table for each record in the associated tables. I thought about concatenate, but I need the data from the associated tables to be displayed individually. Not sure what to try next. Any help is much appreciated.
Sorry, and there is no way to do that like you want. JOIN's can't do that.
I suggest to keep solution with separate queries.
Btw - You could play with UNION operator,
http://en.wikipedia.org/wiki/Union_(SQL)#UNION_operator
P.s.
You could extract main data separately, then extract data from related tables at once using UNION. With UNIOM it will give one result row per each row in related table.
In order to join an two of the Detail tables together without generating duplicate rows, you will have to perform the following operation on each one:
Group on the foreign key to the Master table, and aggregate all other columns being projected onto the join.
Numeric columns are commonly aggregated with SUM(), COUNT(), MAX(), and MIN(). MAX() and MIN() are also applicable to character data. A PIVOT operation is also sometimes useful as an aggregation operator for this type of circumstance.
Once you have two of the Detail tables grouped and aggregated in this way, they will join without duplicates. Additional Detail tables can be added to the join by first grouping and aggregating them also, in the same fashion.
I’m stumped on how to display a recordset via a mysql query that will show two different "real" usernames in a history table that has columns for multiple userIDs (ie createdbyUserID, and assignedtoUserID) – I can get one of them via a JOIN, but how do I JOIN etc to show both since they will likely be different username? Some other trick? Is it via sql or some other function/loop?
Currently:
SELECT nxt_act_dev_hist.Created, nxt_act_dev_hist.assignedtoUserID,
nxt_act_dev_hist.createdbyUserID, nxt_user.username
FROM nxt_act_dev_hist
JOIN nxt_user
ON nxt_act_dev_hist.createdbyUserID=nxt_user.UserID
I'm a newbie here if you can't tell.
You can join the same table twice, like this:
select
-- some other fields
createdByUser.UserName as CreatedByUserName,
assignedtoUser.UserName as AssignedToUserName
from
nxt_act_dev_hist
JOIN nxt_user as createdByUser
ON nxt_act_dev_hist.createdbyUserID = createdByUser.UserID
JOIN nxt_user as assignedtoUser
ON nxt_act_dev_hist.createdbyUserID = assignedtoUser.UserID
I'm not a mysql guy, but that should work.