But if I add one more for my query (that not related to this), for example:
I should get nothing
(but it needs to be workable :D)
You can do a GROUP BY, and use HAVING to make sure all desired tag_id's are there:
SELECT sp.perfume_id
FROM sp_tag_to_perfume sp
WHERE sp.tag_id IN (2070, 127)
GROUP BY sp.perfume_id
HAVING COUNT(DISTINCT sp.tag_id) = 2; -- number of tag_id values (in this case 2070 and 127)
This can get all the columns and data containing perfume id 199.
Select * from sp_tag_to_perfume sp where sp.perfume_id=199;
And from tag_id...
Select distinct perfume_id from sp_tag_to_perfume sp where sp.tags_id=127;
You can use distinct keyword to get unique values of the column.
Related
I have the following query which works great but how do I add multiple columns in its select statement? Following is the query:
SELECT ISNULL(
(SELECT DISTINCT a.DatasourceID
FROM [Table1] a
WHERE a.DatasourceID = 5 AND a.AgencyID = 4 AND a.AccountingMonth = 201907), NULL) TEST
So currently I only get one column (TEST) but would like to add other columns such as DataSourceID, AgencyID and AccountingMonth.
If you want to output a row for some condition (or requested values ) and output a row when it does not meet condition,
you can set a pseudo table for your requested values in the FROM clause and make a left outer join with your Table1.
SELECT ISNULL(Table1.DatasourceId, 999999),
Table1.AgencyId,
Table1.AccountingMonth,
COUNT(*) as count
FROM ( VALUES (5, 4, 201907 ),
(6, 4, 201907 ))
AS requested(DatasourceId, AgencyId, AccountingMonth)
LEFT OUTER JOIN Table1 ON requested.agencyid=Table1.AgencyId
AND requested.datasourceid = Table1.DatasourceId
AND requested.AccountingMonth = Table1.AccountingMonth
GROUP BY Table1.DatasourceId, Table1.AgencyId, Table1.AccountingMonth
Note that:
I have put a ISNULL for the first column like you did to output a particular value (9999) when no value is found.
I did not put the ISNULL(...,NULL) like your query in the other columns since IMHO it is not necessary: if there is no value, a null will be output anyway.
I added a COUNT(*) column to illustrate an aggregate, you could use another (SUM, MIN, MAX) or none if you do not need it.
The set of requested values is provided as a constant table values (see https://learn.microsoft.com/en-us/sql/t-sql/queries/table-value-constructor-transact-sql?view=sql-server-2017)
I have added multiple rows for requested conditions : you can request for multiple datasources, agencies or months in one query with one line for each in the output.
If you want only one row, put only one row in "requested" pseudo table values.
There must be a GROUP BY, even if you do not want to use an aggregate (count, sum or other) in order to have the same behavior as your distinct clause , it restricts the output to single lines for requested values.
To me it seems that you want to see does data exists, i guess that your's AgencyID is foreign key to agency table, DataSourceID also to DataSource, and that you have AccountingMonth table which has all accounting periods:
SELECT ds.ID as DataSourceID , ag.ID as AgencyID , am.ID as AccountingMonth ,
ISNULL(COUNT(a.*),0) as Count
FROM [Table1] a
RIGHT JOIN [Datasource] ds ON ds.ID = a.DataSourceID
RIGHT JOIN [Agency] ag ON ag.ID = a.AgencyID
RIGHT JOIN [AccountingMonth] am on am.ID = a.AccountingMonth
GROUP BY ds.ID, ag.ID, am.ID
In this way you can see count of records per group by criteria. Notice RIGHT join, you must use RIGHT JOIN if you want to include all record from "Right" table.
In yours query you have DISTINCT a.DatasourceID and WHERE a.DatasourceID = 5 and it returns 5 if in table exists rows that match yours WHERE criteria, and returns null if there is no data. If you remove WHERE a.DatasourceID = 5 your query would break with error: subquery returned multiple rows.
the way you are doing only allows for one column and one record and giving it the name of test. It does not look like you really need to test for null. because you are returning null so that does nothing to help you. Remove all the null testing and return a full recordset distinct will also limit your returns to 1 record. When working with a single table you don't need an alias, if there are no spaces or keywords braced identifiers not required. if you need to see if you have an empty record set, test for it in the calling program.
SELECT DatasourceID, AgencyID,AccountingMonth
FROM Table1
WHERE DatasourceID = 5 AND AgencyID = 4 AND AccountingMonth = 201907
Is it possible to use the input from one field of the database for another query in combination with the IN statement. The point is that in the sting, I use for IN, contains several by comma separated values:
SELECT id, name
FROM refPlant
WHERE id IN (SELECT cover
FROM meta_characteristic
WHERE id = 2);
the string of the subquery is: 1735,1736,1737,1738,1739,1740,1741,1742,1743,1744
The query above give me only the first element of the string. But when I put the string directly in the query, I get all the ten elements:
SELECT id, name
FROM refPlant
WHERE id IN (735,1736,1737,1738,1739,1740,1741,1742,1743,1744);
Is it possible to have all ten elements and not only one with query like the first one.
My sql version is 10.1.16-MariaDB
You can use FIND_IN_SET in the join condition.
SELECT r.id, r.name
FROM refPlant r
JOIN (SELECT * FROM meta_characteristic m WHERE id=2) m
ON FIND_IN_SET(r.id,m.cover) > 0
If you use a sub-query as in the first code snippet you will get a filter for each row returned from it. It will not work when it returns as a single string field.
SELECT id, name
FROM refPlant
WHERE FIND_IN_SET(id, (SELECT cover
FROM meta_charateristic
WHERE id = 2));
i get 2 names as the output of the first query....
eg: paul,peter
now this should be the input for the second query,
which has to display paul's and peter's email ids....
For nested queries I would strongly recommend WITH clause. It makes long complex queries order of magnitude easier to understand / construct / modify:
WITH
w_users AS( -- you can name it whatever you want
SELECT id
FROM users
WHERE < long condition here >
),
w_other_subquery AS(
...
)
SELECT email_id
FROM ...
WHERE user_id IN (SELECT id FROM w_users)
You can use like this
LIKE
SELECT USER_ID,EMAIL_ID FROM USERS where user_id IN
(SELECT PRODUCT_MEMBERS FROM PRODUCT WHERE PRODUCT_NAME='ICP/RAA');
Just use the IN clause '=' is used for matching one result
You can use In Command to get result
ex:
SELECT email FROM tableName WHERE (Name IN ('paul', 'peter'))
How do I select only 1 row in sybase without using rowcount? I don't have the privilege to set rowcount in sybase. Is there a way to select only 1 row?
For example:
select * from table where name = 'jack'
This returns two rows; how do I select only one row from the result set without using set rowcount?
Try the query:
SELECT TOP 1 * FROM mytable
WHERE name = 'jack'
As you might guess, this selects the TOP 1 matching results. If you wanted more (which you don't here) you could use any number (TOP 100 or TOP 1000, etc).
A more comprehensive example can be found on w3schools: http://www.w3schools.com/Sql/sql_top.asp
There seems to be a reason, why you're getting more than 1 row for "WHERE name = 'jack'", it looks as if the rows differ.
But if, the rows do not differ you can try adding "distinct":
SELECT DISTINCT * FROM TABLE WHERE name = 'jack'
or try with "GROUP BY" statement, then you should type explicitly all columns, eg.:
SELECT name FROM TABLE WHERE name = 'jack' GROUP BY name
if this is not what you wanted, can you paste here how the 2 rows look exactly?
If you want a single result, use 'GROUP BY' and 'HAVING column = max(column)'. Or replace max() with min().
This should work unless the max or min values are also not unique.
Debugging an app which queries SQL Server 05, can't change the query but need to optimise things.
Running all the selects seperately are quick <1sec, eg: select * from acscard, select id from employee... When joined together it takes 50 seconds.
Is it better to set uninteresting accesscardid fields to null or to '' when using EXISTS?
SELECT * FROM ACSCard
WHERE NOT EXISTS
( SELECT Id FROM Employee
WHERE Employee.AccessCardId = ACSCard.acs_card_number )
AND NOT EXISTS
( SELECT Id FROM Visit
WHERE Visit.AccessCardId = ACSCard.acs_card_number )
ORDER by acs_card_id
Do you have indexes on Employee.AccessCardId, Visit.AccessCardId, and ACSCard.acs_card_number?
The SELECT clause is not evaluated in an EXISTS clause. This:
WHERE EXISTS(SELECT 1/0
FROM EMPLOYEE)
...should raise an error for dividing by zero, but it won't. But you need to put something in the SELECT clause for it to be a valid query - it doesn't matter if it's NULL or a zero length string.
In SQL Server, NOT EXISTS (and NOT IN) are better than the LEFT JOIN/IS NULL approach if the columns being compared are not nullable (the values on either side can not be NULL). The columns compared should be indexed, if they aren't already.