I have a table with columns CompanyID, EmployeeCode. EmployeeCode is unique and CompanyID can be repeated. So we can keep a list of employees in Google, Apple etc.
I want a way to ensure that the same employee cannot be added if he/she is already in the database. What would be a good way to do this ? I'd prefer not to create additional columns or tables for this.
Create a UNIQUE constraint on the column where you want to prevent duplicates:
CREATE UNIQUE INDEX [IX_YourTableName_EmployeeCode] ON [YourTableName] (EmployeeCode)
Try this..
Create table UniqueTable
(
CompanyID int,
EmployeeCode int
)
--Insert dummy data
INSERT INTO UniqueTable(EmployeeCode ,CompanyID ) Values(1,200)
--When are Going to insert duplicate Ecmployeecode '1' then it will not insert data into table
INSERT INTO UniqueTable(EmployeeCode ,CompanyID )
Select 1,200 From UniqueTable t1
Left join UniqueTable t2 on 1=t2.EmployeeCode
WHERE t2.EmployeeCode IS NULL
--We are Going to insert different Ecmployeecode '2' it will insert into table
INSERT INTO UniqueTable(EmployeeCode ,CompanyID )
Select 2,300 From UniqueTable t1
Left join UniqueTable t2 on 2=t2.EmployeeCode
WHERE t2.EmployeeCode IS NULL
Try this
Create PROCEDURE [dbo].[sp_Emp_Insert]
#EmployeeCode nvarchar(50)
As
Begin
if Not Exists (select EmployeeCode from YOUR_TABlE where EmployeeCode =#EmployeeCode )
Begin
Insert QUERY
End
else
Return 0
End
End
Related
I perform steps:
Create temporal table and fill it with data and unique order column [_oid]
Insert everything from temporal table into real table except fictional [_oid], outputting generated [id]'s
Return those generated [id]'s along with corresponding [_oid]
SQL:
CREATE TABLE #temp
(
[Hash] INT NOT NULL,
[Size] INT NOT NULL,
[Data] NVARCHAR(MAX),
[_oid] INT NOT NULL
)
--here insert data into #temp--
INSERT [dbo].[TestObjects]
OUTPUT INSERTED.[Id]
SELECT [Hash], [Size], [Data]
FROM #temp
DROP TABLE #temp
How I can return ([Id], [_oid]) rows ? ....Or at least return [Id] ordered by [_oid] ?
I know insert does not preserve order of inserted items in it's output, but still...
I think you what you are asking for is INSERT INTO, as so:
INSERT INTO [dbo].[TestObjects]
SELECT Hash, Size, Data FROM #temp
ORDER BY _oid
But as you say, there's no guarantee about order when you select from TestObjects, so if it's important can you not have a field in TestObjects you can ORDER BY when you SELECT from it?
IF your insert into #temp is such that both o_id and (hash,size,data) are unique for each row (ie keys), then you could retrieve the inserted o_id from #temp:
select t.[_oid],to.[Id]
from #temp t
inner join [dbo].[TestObjects] to
on t.Hash=to.Hash and t.Size=to.Size and t.data=to.data
As noted by George Menoutis, I did merge:
MERGE [dbo].[TestObjects] AS T_Base
USING #temp AS T_Source
ON (0<>0)
WHEN NOT MATCHED THEN INSERT ([Hash],[Size],[Data]) VALUES (T_Source.[Hash],T_Source.[Size],T_Source.[Data])
OUTPUT INSERTED.[Id], T_Source.[_oid];
If anyone have better approach - feel free to contribute to this answer.
I am trying to get column names from 2 diff tables in diff db and compare them to see if there is any extra column in any table. They should match exactly. One possible solution could be getting all the column names from both table and dump in a temp table side by side and compare? Pls help.
IF OBJECT_ID('tempdb..#myTable') IS NOT NULL DROP TABLE #myTable
CREATE table #myTable (
table1 varchar(100) null,
table2 varchar(100) null
)
INSERT INTO #myTable (table1)
SELECT name
FROM sys.columns
WHERE object_id = OBJECT_ID('table1')
select * from #mytable
DROP TABLE #mytable
I modified your query to this
IF OBJECT_ID('tempdb..#myTable') IS NOT NULL DROP TABLE #myTable
CREATE table #myTable
(
rowNum int IDENTITY(1,1),
table1 varchar(100) null
)
GO
IF OBJECT_ID('tempdb..#myTable2') IS NOT NULL DROP TABLE #myTable2
CREATE table #myTable2
(
rowNum int IDENTITY(1,1),
table2 varchar(100) null
)
GO
USE database1 --your 1st database name here
GO
INSERT INTO #myTable (table1)
(
SELECT
name
FROM sys.columns
WHERE object_id = OBJECT_ID('Table_1'))
GO
USE database2 -- your 2nd database name here
GO
INSERT INTO #myTable2 (table2)
(
SELECT
name
FROM sys.columns
WHERE object_id = OBJECT_ID('Table_2'))
GO
SELECT table1,table2
FROM #myTable m
FULL OUTER JOIN #myTable2 m2 ON m.rowNum = m2.rowNum
ORDER BY table1,table2
DROP TABLE #mytable
DROP TABLE #mytable2
Hi I am newbie to SQL trigger. since I tried and searched on online and I dont find any clear outcome.
so here is my problem.
I have three tables:
TABLE1 :
ID NAME (columns )
1 prabhu
TABLE2 :
Id COUNTRY (columns )
1 India
I want this to send to log table if anything like insert/update happen in table2
The SQL(DB2) trigger has to do the following and the result should be in log table like this
LOGTABLE:
ID NAME COUNTRY
1 prabhu India
Your help really appreciated.
Try this,
-- Create tables
create table table1(id int, empName varchar(20));
create table table2(id int, country varchar(20));
create table logtable(id int, empName varchar(20), country varchar(20));
-- Create trigger
CREATE TRIGGER logtableAfterInsert ON table2
after INSERT,DELETE,UPDATE
AS
BEGIN
declare #empid int;
declare #empname2 varchar(20);
declare #empcountry varchar(20);
select #empid=i.id from inserted i;
select #empcountry=i.country from inserted i;
select #empname2=tbl1.empName from table1 tbl1 where tbl1.id=#empid;
insert into logtable values(#empid,#empname2,#empcountry);
PRINT 'Inserted'
END
GO
After that insert the values,
insert into table1 values(1, 'prabhu');
insert into table2 values (1, 'India');
Check the results,
select * from table1;
select * from table2;
select * from logtable;
Hope this resolves...
BTW, You need to add the foreign key constraint.
CREATE OR REPLACE TRIGGER logtableAfterUpdate
AFTER UPDATE ON table2
REFERENCING NEW AS NAUDIT OLD AS OAUDIT
FOR EACH ROW MODE DB2SQL
--BEGIN --ATOMIC
insert into logtable
values(
(select id from table2 tbl2 where tbl2.id =OAUDIT.id),
(select empName from table1 tbl1 where tbl1.id=(select id from table2 tbl2 where tbl2.id =OAUDIT.id)),
(select country from table2 tbl2 where tbl2.id =OAUDIT.id)
);
--END;
I have a temp table declared
declare #tmptable(
value nvarchar(500) not null
);
I use a function to insert values into that temp table.
I am trying to figure out how to update a table using the values of #tmptable
insert into t1 (
active
,SchoolId
,inserted
)
select
1
,temp.value
,#insertedDate
select temp.value from #tmptable;
When i try to insert in table t1 it doesn't work. I guess there are two Select statements is causing the problem. Please let me know how to fix it. Thanks
Try this one -
INSERT INTO dbo.t1
(
Active
, SchoolId
, Inserted
)
SELECT
1
, t.value
, #insertedDate
FROM #tmptable t;
INSERT INTO t1
(
ACTIVE
,SchoolId
,INSERTED
)
SELECT 1
,temp.value
,#insertedDate
FROM #tmptable temp;
insert into t1 (
active
,SchoolId
,inserted
)
select
1
,temp.value
,#insertedDate
from #tmptable;
this will work...
I have multiple groups of duplicates in one table (3 records for one, 2 for another, etc) - multiple rows where more than 1 exists.
Below is what I came up with to delete them, but I have to run the script for however many duplicates there are:
set rowcount 1
delete from Table
where code in (
select code from Table
group by code
having (count(code) > 1)
)
set rowcount 0
This works well to a degree. I need to run this for every group of duplicates, and then it only deletes 1 (which is all I need right now).
If you have a key column on the table, then you can use this to uniquely identify the "distinct" rows in your table.
Just use a sub query to identify a list of ID's for unique rows and then delete everything outside of this set. Something along the lines of.....
create table #TempTable
(
ID int identity(1,1) not null primary key,
SomeData varchar(100) not null
)
insert into #TempTable(SomeData) values('someData1')
insert into #TempTable(SomeData) values('someData1')
insert into #TempTable(SomeData) values('someData2')
insert into #TempTable(SomeData) values('someData2')
insert into #TempTable(SomeData) values('someData2')
insert into #TempTable(SomeData) values('someData3')
insert into #TempTable(SomeData) values('someData4')
select * from #TempTable
--Records to be deleted
SELECT ID
FROM #TempTable
WHERE ID NOT IN
(
select MAX(ID)
from #TempTable
group by SomeData
)
--Delete them
DELETE
FROM #TempTable
WHERE ID NOT IN
(
select MAX(ID)
from #TempTable
group by SomeData
)
--Final Result Set
select * from #TempTable
drop table #TempTable;
Alternatively you could use a CTE for example:
WITH UniqueRecords AS
(
select MAX(ID) AS ID
from #TempTable
group by SomeData
)
DELETE A
FROM #TempTable A
LEFT outer join UniqueRecords B on
A.ID = B.ID
WHERE B.ID IS NULL
It is frequently more efficient to copy unique rows into temporary table,
drop source table, rename back temporary table.
I reused the definition and data of #TempTable, called here as SrcTable instead, since it is impossible to rename temporary table into a regular one)
create table SrcTable
(
ID int identity(1,1) not null primary key,
SomeData varchar(100) not null
)
insert into SrcTable(SomeData) values('someData1')
insert into SrcTable(SomeData) values('someData1')
insert into SrcTable(SomeData) values('someData2')
insert into SrcTable(SomeData) values('someData2')
insert into SrcTable(SomeData) values('someData2')
insert into SrcTable(SomeData) values('someData3')
insert into SrcTable(SomeData) values('someData4')
by John Sansom in previous answer
-- cloning "unique" part
SELECT * INTO TempTable
FROM SrcTable --original table
WHERE id IN
(SELECT MAX(id) AS ID
FROM SrcTable
GROUP BY SomeData);
GO;
DROP TABLE SrcTable
GO;
sys.sp_rename 'TempTable', 'SrcTable'
You can alternatively use ROW_NUMBER() function to filter out duplicates
;WITH [CTE_DUPLICATES] AS
(
SELECT RN = ROW_NUMBER() OVER (PARTITION BY SomeData ORDER BY SomeData)
FROM #TempTable
)
DELETE FROM [CTE_DUPLICATES] WHERE RN > 1
SET ROWCOUNT 1
DELETE Table
FROM Table a
WHERE (SELECT COUNT(*) FROM Table b WHERE b.Code = a.Code ) > 1
WHILE ##rowcount > 0
DELETE Table
FROM Table a
WHERE (SELECT COUNT(*) FROM Table b WHERE b.Code = a.Code ) > 1
SET ROWCOUNT 0
this will delete all duplicate rows, But you can add attributes if you want to compare according to them .