Is there a way to insert a new record to a table that has an non-unique id and set this id to the next number in the same SQL statement?
Something like
INSERT INTO T1 (id, fname, lname)
VALUES ([last id + 1], 'Dan', 'Thomson');
this probably works
INSERT INTO T1 (id, fname, lname)
VALUES (ifnull((select max(id) from T1),0) + 1, 'Dan', 'Thomson')
DECLARE #COUNTER INT;
SET #COUNTER = 1;
WHILE(#COUNTER <= XXX)
BEGIN
INSERT INTO T1 (id, fname, lname)
VALUES (#COUNTER, #FNAME , #LNAME);
SET #COUNTER = #COUNTER + 1;
END
Built-in function MAX :
INSERT INTO T1 (id, fname, lname)
SELECT ifnull(MAX(id)+ 1,1), 'Dan', 'Thomson' FROM T1
Insert and set value with max()+1 problems
SELECT MAX(col) +1 is not safe -- it does not ensure that you aren't inserting more than one customer with the same customer_id value, regardless if selecting from the same table or any others.
For performance, add an index:
CREATE INDEX T1_INDEX1 ON T1 (id) DESC
References:
MAX()
CREATE INDEX
Index Advisor, Show Statements
Accelerated analytics - faster aggregations using the IBM DB2 for i encoded vector index (EVI) technology
Unit Test
-- Create Table
SET SCHEMA QTEMP;
CREAT TABLE testtbl (
id integer not null default,
fname char(10) not null default,
lname char(10) not null default)
;
-- Initialize Table with Data
insert into
testtbl ( id , fname, lname)
values
( 1, 'fname1', 'lname_1'),
( 2, 'fname2', 'lname_2'),
( 2, 'fname3', 'lname_3'),
( 3, 'fname4', 'lname_4')
;
-- Test Insert Statement
INSERT INTO
testtbl ( id, fname, lname )
SELECT ifnull(MAX( id ) + 1, 1), 'Dan', 'Thomson' FROM testtbl;
--Confirm Expectation
select * from testtbl;
ID FNAME LNAME
-------------------------------------
1 fname1 lname_1
2 fname2 lname_2
3 fname4 lname_4
4 Dan Thomson
if you want insert all content of table with unique id start with max +1
INSERT INTO T1 (id, fname, lname)
select
rownumber() over() + ifnull((select max(T1.id) from T1), 0),
T2.zone1, T2.zone2
from T2
Related
My script is as below
CREATE TABLE #t (Id int, Name varchar(10))
INSERT INTO #t VALUES (1, 'A')
INSERT INTO #t VALUES (1, 'B')
INSERT INTO #t VALUES (1, 'C')
INSERT INTO #t VALUES (1, 'D')
INSERT INTO #t VALUES (2, 'E')
SELECT COUNT(0)FROM (SELECT COUNT(0) FROM #t GROUP BY Id) a
but I am getting an error
Msg 8155, Level 16, State 2, Line 5
No column name was specified for column 1 of 'A'.
When you use a subquery, all the columns need to given names:
SELECT COUNT(0)
FROM (SELECT COUNT(0) as cnt FROM #t GROUP BY Id
) a;
However, a simpler way to write this is:
SELECT COUNT(DISTINCT id)
FROM #t;
Actually, this isn't exactly the same. Your version will count NULL values but this does not. The exact equivalent is:
SELECT COUNT(DISTINCT id) + MAX(CASE WHEN id IS NULL THEN 1 ELSE 0 END)
FROM #t;
I'm new to sql and trying to find out if there is a way to say something like this in isqlplus? I'm trying to insert a row with values if a certain value exists on another table.
IF EXISTS (SELECT ID FROM SOMETABLE WHERE ID = 1)
BEGIN
INSERT INTO ANOTHERTABLE (NBR, FNAME, LNAME) VALUES ( 2, 'John', 'Smith');
END
Any help appreciated.
You can add WHERE EXISTS in your query
INSERT INTO ANOTHERTABLE (NBR, FNAME, LNAME)
SELECT 2, 'John', 'Smith'
FROM DUAL
WHERE EXISTS (SELECT ID FROM SOMETABLE WHERE ID = 1)
I have two tables. First one is student table where he can select two optional courses and other table is current semester's optional courses list.
When ever the student selects a course, row is inserted with basic details such as roll number, inserted time, selected course and status as "1". When ever a selected course is de-selected the status is set as "0" for that row.
Suppose the student has select course id 1 and 2.
Now using this query
select SselectedCourse AS [text()] FROM Sample.dbo.Tbl_student_details where var_rollnumber = '020803009' and status = 1 order by var_courseselectedtime desc FOR XML PATH('')
This will give me the result as "12" where 1 is physics and 2 is social.
the second table holds the value from 1-9
For e.g course id
1 = physics
2 = social
3 = chemistry
4 = geography
5 = computer
6 = Spoken Hindi
7 = Spoken English
8 = B.EEE
9 = B.ECE
now the current student has selected 1 and 2. So on first column, i get "12" and second column i need to get "3456789"(remaining courses).
How to write a query for this?
This is not in single query but is simple.
DECLARE #STUDENT AS TABLE(ID INT, COURSEID INT)
DECLARE #SEM AS TABLE (COURSEID INT, COURSE VARCHAR(100))
INSERT INTO #STUDENT VALUES(1, 1)
INSERT INTO #STUDENT VALUES(1, 2)
INSERT INTO #SEM VALUES(1, 'physics')
INSERT INTO #SEM VALUES(2, 'social')
INSERT INTO #SEM VALUES(3, 'chemistry')
INSERT INTO #SEM VALUES(4, 'geography')
INSERT INTO #SEM VALUES(5, 'computer')
INSERT INTO #SEM VALUES(6, 'Spoken Hindi')
INSERT INTO #SEM VALUES(7, 'Spoken English')
INSERT INTO #SEM VALUES(8, 'B.EEE')
INSERT INTO #SEM VALUES(9, 'B.ECE')
DECLARE #COURSEIDS_STUDENT VARCHAR(100), #COURSEIDS_SEM VARCHAR(100)
SELECT #COURSEIDS_STUDENT = COALESCE(#COURSEIDS_STUDENT, '') + CONVERT(VARCHAR(10), COURSEID) + ' ' FROM #STUDENT
SELECT #COURSEIDS_SEM = COALESCE(#COURSEIDS_SEM , '') + CONVERT(VARCHAR(10), COURSEID) + ' ' FROM #SEM WHERE COURSEID NOT IN (SELECT COURSEID FROM #STUDENT)
SELECT #COURSEIDS_STUDENT COURSEIDS_STUDENT, #COURSEIDS_SEM COURSEIDS_SEM
try this:
;WITH CTE as (select ROW_NUMBER() over (order by (select 0)) as rn,* from Sample.dbo.Tbl_student_details)
,CTE1 As(
select rn,SselectedCourse ,replace(stuff((select ''+courseid from course_details for xml path('')),1,1,''),SselectedCourse,'') as rem from CTE a
where rn = 1
union all
select c2.rn,c2.SselectedCourse,replace(rem,c2.SselectedCourse,'') as rem
from CTE1 c1 inner join CTE c2
on c2.rn=c1.rn+1
)
select STUFF((select ''+SselectedCourse from CTE1 for xml path('')),1,0,''),(select top 1 rem from CTE1 order by rn desc)
i want to delete duplicate rows from my table on the basis of category ID, but don't want to delete all, i want to left one rows if there are more than one row with the same category ID.
this is my query i am making i need to change it.
delete from twinhead_tblcategory where categoryid in (select categoryid from twinhead_tblcategory group by categoryid having count(categoryid) > 1 )
For SQL Server you can do it:
WITH MyTableCTE (CategoryId, RowNumber)
AS
(
SELECT CategoryId, ROW_NUMBER() OVER (ORDER BY CategoryId) AS 'RowNumber'
FROM MyTable
)
Delete From MyTableCTE Where RowNumber > 1
Do a select distinct into a new table, delete the old one and rename the new one into old table name.
If your rows have a distinct id column, then this should work:
DELETE t1 FROM your_table t1, your_table t2
WHERE t1.column1 = t2.column1 AND t1.column2 = t2.column2
AND ... /* check equality of all relevant columns */
AND t1.id < t2.id
Check here for sql server - http://support.microsoft.com/kb/139444 - that should get you started.
This is probably heavy-handed but perhaps you could select distinct * into a temp table, then truncate the table, then insert into the table the contents of the temp table. Foreign key constraints may prevent this, though.
For SqlServer, you could use a cursor to loop through all items, ordered by that categoryID.
Is the current ID the same as the previous one? Then delete it, see example C of this article.
Else remember the ID for the next round.
You have several way for delete duplicate rows.
for my solutions , first consider this table for example
CREATE TABLE #Employee
(
ID INT,
FIRST_NAME NVARCHAR(100),
LAST_NAME NVARCHAR(300)
)
INSERT INTO #Employee VALUES ( 1, 'Vahid', 'Nasiri' );
INSERT INTO #Employee VALUES ( 2, 'name1', 'lname1' );
INSERT INTO #Employee VALUES ( 3, 'name2', 'lname2' );
INSERT INTO #Employee VALUES ( 2, 'name1', 'lname1' );
INSERT INTO #Employee VALUES ( 3, 'name2', 'lname2' );
INSERT INTO #Employee VALUES ( 4, 'name3', 'lname3' );
First solution : Use another table for duplicate rows.
SELECT DISTINCT *
FROM #Employee
SELECT * INTO #DuplicateEmployee
FROM #Employee
INSERT #DuplicateEmployee
SELECT DISTINCT *
FROM #Employee
BEGIN TRAN
DELETE #Employee
INSERT #Employee
SELECT *
FROM #DuplicateEmployee
COMMIT TRAN
DROP TABLE #DuplicateEmployee
SELECT DISTINCT *
FROM #Employee
Second solution :
SELECT DISTINCT * FROM #Employee
SELECT * INTO #DuplicateEmployee FROM #Employee
INSERT #DuplicateEmployee
SELECT ID,
FIRST_NAME,
LAST_NAME
FROM #Employee
GROUP BY
ID,FIRST_NAME,LAST_NAME
HAVING COUNT(*) > 1
BEGIN TRAN
DELETE #Employee
FROM #DuplicateEmployee
WHERE #Employee.ID = #DuplicateEmployee.ID
AND #Employee.FIRST_NAME = #DuplicateEmployee.FIRST_NAME
AND #Employee.LAST_NAME = #DuplicateEmployee.LAST_NAME
INSERT #Employee
SELECT *
FROM #DuplicateEmployee
COMMIT TRAN
DROP TABLE #DuplicateEmployee
SELECT DISTINCT * FROM #Employee
teared solution : use rowcount
SELECT DISTINCT *
FROM #Employee
SET ROWCOUNT 1
SELECT 1
WHILE ##rowcount > 0
DELETE #Employee
WHERE 1 < (
SELECT COUNT(*)
FROM #Employee a2
WHERE #Employee.ID = a2.ID
AND #Employee.FIRST_NAME = a2.FIRST_NAME
AND #Employee.LAST_NAME = a2.LAST_NAME
)
SET ROWCOUNT 0
SELECT DISTINCT *
FROM #Employee
Fourth solution : use Analytical Functions
SELECT DISTINCT *
FROM #Employee;
WITH #DeleteEmployee AS (
SELECT ROW_NUMBER()
OVER(PARTITION BY ID, First_Name, Last_Name ORDER BY ID) AS
RNUM
FROM #Employee
)
DELETE
FROM #DeleteEmployee
WHERE RNUM > 1
SELECT DISTINCT *
FROM #Employee
Fifth solution : Use identity field
SELECT DISTINCT *
FROM #Employee;
ALTER TABLE #Employee ADD UNIQ_ID INT IDENTITY(1, 1)
DELETE
FROM #Employee
WHERE UNIQ_ID < (
SELECT MAX(UNIQ_ID)
FROM #Employee a2
WHERE #Employee.ID = a2.ID
AND #Employee.FIRST_NAME = a2.FIRST_NAME
AND #Employee.LAST_NAME = a2.LAST_NAME
)
ALTER TABLE #Employee DROP COLUMN UNIQ_ID
SELECT DISTINCT *
FROM #Employee
and end of all solution use this command
DROP TABLE #Employee
Source of my answer is this site
I have 2 tables: sets and groups. Both are joined using a 3rd table set_has_groups.
I would like to get sets that have ALL groups that I specify
One way of doing it would be
SELECT column1, column2 FROM sets WHERE
id IN(SELECT set_id FROM set_has_group WHERE group_id = 1)
AND id IN(SELECT set_id FROM set_has_group WHERE group_id = 2)
AND id IN(SELECT set_id FROM set_has_group WHERE group_id = 3)
obviously this is not the most beautiful solution
I've also tried this:
SELECT column1, column2 FROM sets WHERE
id IN(SELECT set_id FROM set_has_group WHERE group_id IN(1,2,3) GROUP BY group_id
HAVING COUNT(*) = 3
This looks prettier but the problem is that it takes forever to execute.
While the first query runs in like 200ms the 2nd one takes more than 1 minute.
Any idea why that is?
===UPDATE:
I've played with this some more and I modified the 2nd query like this
SELECT columns FROM `set` WHERE id IN(
select set_id FROM
(
SELECT set_id FROM set_has_group
WHERE group_id IN(1,2,3)
GROUP BY set_id HAVING COUNT(*) = 3
) as temp
)
that is really fast
It's the same as the 2nd query before just that I wrap it in another temporary table
Pretty strange
I am suspecting a small mistyping in the second query.
Really, I am not sure. Probably, the second query is executed via full table scan. At the same time the first one "IN" is really transformed into "EXISTS". So, you can try to use "exists". For example:
...
where 3 = (select count(*) from set_has_group
where group_id in (1, 2, 3) and set_id = id
group by set_id)
Assuming SQL Server, here is a working example with a JOIN that should work better than the IN clauses you are using as long as you have your primary and foreign keys set correctly. I have built joined 5 sets to 3 groups, but set 4 and 5 are not a part of group 3 and will not show in the answer. However, this query is not scalable (for ex. find in group 4, 5, 7, 8 and 13 will require code modifications unless you parse input params into a table variable)
set nocount on
declare #sets table
(
Id INT Identity (1, 1),
Column1 VarChar (50),
Column2 VarChar (50)
)
declare #Set_Has_Group table
(
Set_Id Int,
Group_Id Int
)
insert into #sets values (newid(), newid())
insert into #sets values (newid(), newid())
insert into #sets values (newid(), newid())
insert into #sets values (newid(), newid())
insert into #sets values (newid(), newid())
update #sets set column1 = 'Column1 at Row ' + Convert (varchar, id)
update #sets set column2 = 'Column2 at Row ' + Convert (varchar, id)
insert into #Set_Has_Group values (1, 1)
insert into #Set_Has_Group values (1, 2)
insert into #Set_Has_Group values (1, 3)
insert into #Set_Has_Group values (2, 1)
insert into #Set_Has_Group values (2, 2)
insert into #Set_Has_Group values (2, 3)
insert into #Set_Has_Group values (3, 1)
insert into #Set_Has_Group values (3, 2)
insert into #Set_Has_Group values (3, 3)
insert into #Set_Has_Group values (4, 1)
insert into #Set_Has_Group values (4, 2)
insert into #Set_Has_Group values (5, 1)
insert into #Set_Has_Group values (5, 2)
/* your query with IN */
SELECT column1, column2 FROM #sets WHERE
id IN(SELECT set_id FROM #set_has_group WHERE group_id = 1)
AND id IN(SELECT set_id FROM #set_has_group WHERE group_id = 2)
AND id IN(SELECT set_id FROM #set_has_group WHERE group_id = 3)
/* my query with JOIN */
SELECT * -- Column1, Column2
FROM #sets sets
WHERE 3 = (
SELECT Count (1)
FROM #Set_Has_Group Set_Has_Group
WHERE 1=1
AND sets.Id = Set_Has_Group.Set_Id
AND Set_Has_Group.Group_ID IN (1, 2, 3)
Group by Set_Id
)
Here's a solution that uses a non-correlated subquery and no GROUP BY:
SELECT column1, column2
FROM sets
WHERE id IN (
SELECT g1.set_id FROM set_has_group g1
JOIN set_has_group g2 ON (g1.set_id = g3.set_id)
JOIN set_has_group g3 ON (g1.set_id = g3.set_id)
WHERE g1.group_id = 1 AND g2.group_id = 2 AND g3.group_id = 3);