I know I haven't framed the question very well, to be honest I found it difficult to explain without an example.
I have a table with SalesPersonID and SalesPersonSSN fields.
My requirement is a SalesPersonID should only exist with one SalesPersonSSN and vice versa.
If you see the table (sample data), the record with SalesPersonID 2003 is invalid because SalesPersonSSN 3344556677 already exists with SalesPersonID 2001. Similarly SalesPersonID 2001 should never exist with other than 3344556677.
I don't know how to enforce this rule in the table.
Also is there a simple query to find out if the rule is violated.
You want unique constraint :
alter table t
add constraint ssn unique(SalesPersonSSN);
If you want the data that violates the rules you can use exists :
select t.*
from table t
where exists (select 1
from table t1
where t1.SalesPersonSSN = t.SalesPersonSSN and
t1.SalesPersonID <> t.SalesPersonID
);
To find out if your rule is violated you could use the follwowing
Table
DECLARE #t TABLE (SalesPersonId INT, SalesPersonSSN VARCHAR(255))
INSERT INTO #t VALUES (2001,'3344556677'), (2002,'7755330099'), (2003,'3344556677')
Query
SELECT t.*
FROM #t t
INNER JOIN (SELECT SalesPersonSSN
FROM #t
GROUP BY SalesPersonSSN
HAVING COUNT(*) > 1
) a
ON a.SalesPersonSSN = t.SalesPersonSSN
You need to write the complete logic for it:
declare #ssn as varchar(255)='7755330099' --INPUT
declare #pid as int=201 --INPUT
declare #ssn1 as varchar(255)--local variable
declare #pid1 as int --local variable
select #pid1=SalesPersonId from #t where SalesPersonSSN=#ssn;
select #ssn1=SalesPersonSSN from #t where SalesPersonId=#pid;
if(#pid1 is not null and #pid1<>#pid)
begin
print('failed: as person '+cast(#pid1 as varchar(255))+' already asigned to ssn#'+#ssn)
end
if(#ssn1 is not null and #ssn1<>#ssn)
begin
print('failed: as ssn#'+#ssn1 +' already asigned to pid# '+cast(#pid as varchar(255)))
end
Table definition:
create TABLE #t(SalesPersonId INT, SalesPersonSSN VARCHAR(255))
INSERT INTO #t VALUES (2001,'3344556677'), (2002,'7755330099'), (2003,'3344556677')
I have a condition like this:
IF #aaa = 'high'
set #bbb = select * from table1
else
set #bbb = select * from table2
I am going to use this variable (#bbb) throughout my stored procedure
is this possible to save a table into a variable?
I tried using temporary table but i am not able to assign it twice.
IF #aaa = 'high'
set #bbb = select * into #temp from table1
else
set #bbb = select * into #temp from table2
it shows #temp is already declared.
No, It is not work like that. You can declare a table variable and insert into inside it.
DECLARE #bbbTable TABLE(
Id int NOT NULL,
SampleColumn varchar(50) NOT NULL
);
insert into #bbbTable (Id,SampleColumn)
select Id,SampleColumn from table1
If the table1 and table2 are completely different tables, you should declare two different table variable;
DECLARE #bbbTable TABLE(
Id int NOT NULL,
SampleColumn varchar(50) NOT NULL
);
DECLARE #aaaTable TABLE(
Id int NOT NULL,
SampleColumn varchar(50) NOT NULL
);
IF #aaa = 'high'
insert into #bbbTable (Id,SampleColumn)
select Id,SampleColumn from table1
else
insert into #aaaTable (Id,SampleColumn)
select Id,SampleColumn from table2
You cant insert into a variable more than 1 value.
you can use Table Variable to reach your answer like this:
DELCARE #TableResult AS TABLE (Column1 INT, Column2 INT)
IF #aaa = 'high'
BEGIN
INSERT INTO #TableResult (Column1,Column2)
SELECT Column1FromTable, Column2FromTable
FROM table1
END
ELSE
BEGIN
INSERT INTO #TableResult (Column1,Column2)
SELECT Column1FromTable, Column2FromTable
FROM table2
END
Of course you can declare more than 2 columns.
You can store only 1 Column/Row to a variable.So you can't say *.
Suppose I want to store the value of Column1 from TableA to a variable, I can use this
SELECT #MyVariable = Column1 FROM TableA
But I Can't Say
SELECT #MyVariable = * FROM TableA
Even if there is only 1 column in the Table TableA.
Also If there is more than 1 record returned by the Select condition, then it will assign the First value to the Variable.
Or What you need is to store the entire Rows, you can Either use a Temporary table or a table variable.
Temporary Table
SELECT * INTO #Temp FROM TableA
Table Variable
DECLARE #MyVarTable TABLE
(
Column1 VARCHAR(50),
Column2 VARCHAR(50)
)
INSERT INTO #MyVarTable
(
Column1 ,
Column2
)
SELECT
Column1 ,
Column2
From MyTable
This Temporary Table and Table variable can be accessed in the same way you access the normal table using SELECT/UPDATE/DELETE Queries. Except :
Temporary tables are created for each session and automatically dropped when the session ends or the Query window is Closed
Table Variables exists only when you execute the Query. So before using the table variable in a query you need to declare the same
I Have a table below and I will create a new column say named 'Amount'. The existing column 'Id' is foreign key and link the information in a table say 'Loan'('Id' is the primary key of table 'Loan' ). The simple thing I wanna do is assign each new created Amount cell with the right amount obtain from table 'Loan', mapping with 'Id'. I currently use local variable and self-created table type to find the amount value in 'Loan' case by case. Is there any other more efficient way to execute the same operation? Many thanks.
MyTable was as below:
My code was as followed:
ALTER TABLE MyTable
ADD Amount MONEY
CREATE TYPE ListofID AS TABLE (idx INT IDENTITY(1,1), ID VARCHAR(255))
DECLARE #Table_ID_List ListofID
INSERT #Table_ID_List (
ID )
SELECT Id FROM MyTable
DECLARE #i INT
DECLARE #cnt INT
SELECT #i = min(idx) - 1, #cnt = max(idx) FROM #Table_ID_List
DECLARE #app VARCHAR(255)
WHILE #i<#cnt
BEGIN
SELECT #i = #i + 1
SELECT #app = (SELECT ID FROM #Table_ID_List WHERE idx = #i)
UPDATE MyTable
SET Amount =(SELECT Amount FROM Loan WHERE Id = #app)
WHERE Id = #app
END
Depending on the size of your table, you may want to use the SWITCH statement to transfer the whole table at once to the new schema.
https://sqlperformance.com/2012/08/t-sql-queries/t-sql-tuesday-schema-switch-a-roo
I may have missed your question, but I believe you can do this directly via an Update statement. Something along the lines of:
ALTER TABLE MyTable ADD Amount MONEY
UPDATE
t1
SET
t1.Amount = t2.Amount
FROM
MyTable t1
JOIN Loan t2
ON t1.Id = t2.Id
Wouldn't that do the trick?
I have a MASTER table and I'd like to INSERT INTO another table so a straight forward copy. I want to copy this table 3 x times by changing the value of 1 x field called COMP (short for company). In the MASTER table the field COMP contains value MASTER. I'd like to change this value to the 3 x new companies A, B & C.
How & where in the query do I do this?
Much appreciated any assistance!
lets say you have the following table with values and one more table with same schema called AnotherTable
create table MasterTable(
COMP varchar(50),
MoreData varchar(200)
);
And you have the 3 values:
declare #Comp1 varchar(50) = 'AComp', #Comp2 varchar(50) = 'BComp', #Comp3 varchar(50) = 'CComp';
insert into AnotherTable
select #Comp1, MoreData
from MasterTable
union all
select #Comp2, MoreData
from MasterTable
union all
select #Comp3, MoreData
from MasterTable
Now there still be issues of what are your Primary Key, Clustered Index.
Do you have identity in these tables or what is the identifier.
If the tables are huge you will need to do it in 3 inserts
insert into AnotherTable
select #Comp1, MoreData
from MasterTable;
insert into AnotherTable
select #Comp2, MoreData
from MasterTable;
insert into AnotherTable
select #Comp3, MoreData
from MasterTable;
Very simplified, I have two tables Source and Target.
declare #Source table (SourceID int identity(1,2), SourceName varchar(50))
declare #Target table (TargetID int identity(2,2), TargetName varchar(50))
insert into #Source values ('Row 1'), ('Row 2')
I would like to move all rows from #Source to #Target and know the TargetID for each SourceID because there are also the tables SourceChild and TargetChild that needs to be copied as well and I need to add the new TargetID into TargetChild.TargetID FK column.
There are a couple of solutions to this.
Use a while loop or cursors to insert one row (RBAR) to Target at a time and use scope_identity() to fill the FK of TargetChild.
Add a temp column to #Target and insert SourceID. You can then join that column to fetch the TargetID for the FK in TargetChild.
SET IDENTITY_INSERT OFF for #Target and handle assigning new values yourself. You get a range that you then use in TargetChild.TargetID.
I'm not all that fond of any of them. The one I used so far is cursors.
What I would really like to do is to use the output clause of the insert statement.
insert into #Target(TargetName)
output inserted.TargetID, S.SourceID
select SourceName
from #Source as S
But it is not possible
The multi-part identifier "S.SourceID" could not be bound.
But it is possible with a merge.
merge #Target as T
using #Source as S
on 0=1
when not matched then
insert (TargetName) values (SourceName)
output inserted.TargetID, S.SourceID;
Result
TargetID SourceID
----------- -----------
2 1
4 3
I want to know if you have used this? If you have any thoughts about the solution or see any problems with it? It works fine in simple scenarios but perhaps something ugly could happen when the query plan get really complicated due to a complicated source query. Worst scenario would be that the TargetID/SourceID pairs actually isn't a match.
MSDN has this to say about the from_table_name of the output clause.
Is a column prefix that specifies a table included in the FROM clause of a DELETE, UPDATE, or MERGE statement that is used to specify the rows to update or delete.
For some reason they don't say "rows to insert, update or delete" only "rows to update or delete".
Any thoughts are welcome and totally different solutions to the original problem is much appreciated.
In my opinion this is a great use of MERGE and output. I've used in several scenarios and haven't experienced any oddities to date.
For example, here is test setup that clones a Folder and all Files (identity) within it into a newly created Folder (guid).
DECLARE #FolderIndex TABLE (FolderId UNIQUEIDENTIFIER PRIMARY KEY, FolderName varchar(25));
INSERT INTO #FolderIndex
(FolderId, FolderName)
VALUES(newid(), 'OriginalFolder');
DECLARE #FileIndex TABLE (FileId int identity(1,1) PRIMARY KEY, FileName varchar(10));
INSERT INTO #FileIndex
(FileName)
VALUES('test.txt');
DECLARE #FileFolder TABLE (FolderId UNIQUEIDENTIFIER, FileId int, PRIMARY KEY(FolderId, FileId));
INSERT INTO #FileFolder
(FolderId, FileId)
SELECT FolderId,
FileId
FROM #FolderIndex
CROSS JOIN #FileIndex; -- just to illustrate
DECLARE #sFolder TABLE (FromFolderId UNIQUEIDENTIFIER, ToFolderId UNIQUEIDENTIFIER);
DECLARE #sFile TABLE (FromFileId int, ToFileId int);
-- copy Folder Structure
MERGE #FolderIndex fi
USING ( SELECT 1 [Dummy],
FolderId,
FolderName
FROM #FolderIndex [fi]
WHERE FolderName = 'OriginalFolder'
) d ON d.Dummy = 0
WHEN NOT MATCHED
THEN INSERT
(FolderId, FolderName)
VALUES (newid(), 'copy_'+FolderName)
OUTPUT d.FolderId,
INSERTED.FolderId
INTO #sFolder (FromFolderId, toFolderId);
-- copy File structure
MERGE #FileIndex fi
USING ( SELECT 1 [Dummy],
fi.FileId,
fi.[FileName]
FROM #FileIndex fi
INNER
JOIN #FileFolder fm ON
fi.FileId = fm.FileId
INNER
JOIN #FolderIndex fo ON
fm.FolderId = fo.FolderId
WHERE fo.FolderName = 'OriginalFolder'
) d ON d.Dummy = 0
WHEN NOT MATCHED
THEN INSERT ([FileName])
VALUES ([FileName])
OUTPUT d.FileId,
INSERTED.FileId
INTO #sFile (FromFileId, toFileId);
-- link new files to Folders
INSERT INTO #FileFolder (FileId, FolderId)
SELECT sfi.toFileId, sfo.toFolderId
FROM #FileFolder fm
INNER
JOIN #sFile sfi ON
fm.FileId = sfi.FromFileId
INNER
JOIN #sFolder sfo ON
fm.FolderId = sfo.FromFolderId
-- return
SELECT *
FROM #FileIndex fi
JOIN #FileFolder ff ON
fi.FileId = ff.FileId
JOIN #FolderIndex fo ON
ff.FolderId = fo.FolderId
I would like to add another example to add to #Nathan's example, as I found it somewhat confusing.
Mine uses real tables for the most part, and not temp tables.
I also got my inspiration from here: another example
-- Copy the FormSectionInstance
DECLARE #FormSectionInstanceTable TABLE(OldFormSectionInstanceId INT, NewFormSectionInstanceId INT)
;MERGE INTO [dbo].[FormSectionInstance]
USING
(
SELECT
fsi.FormSectionInstanceId [OldFormSectionInstanceId]
, #NewFormHeaderId [NewFormHeaderId]
, fsi.FormSectionId
, fsi.IsClone
, #UserId [NewCreatedByUserId]
, GETDATE() NewCreatedDate
, #UserId [NewUpdatedByUserId]
, GETDATE() NewUpdatedDate
FROM [dbo].[FormSectionInstance] fsi
WHERE fsi.[FormHeaderId] = #FormHeaderId
) tblSource ON 1=0 -- use always false condition
WHEN NOT MATCHED
THEN INSERT
( [FormHeaderId], FormSectionId, IsClone, CreatedByUserId, CreatedDate, UpdatedByUserId, UpdatedDate)
VALUES( [NewFormHeaderId], FormSectionId, IsClone, NewCreatedByUserId, NewCreatedDate, NewUpdatedByUserId, NewUpdatedDate)
OUTPUT tblSource.[OldFormSectionInstanceId], INSERTED.FormSectionInstanceId
INTO #FormSectionInstanceTable(OldFormSectionInstanceId, NewFormSectionInstanceId);
-- Copy the FormDetail
INSERT INTO [dbo].[FormDetail]
(FormHeaderId, FormFieldId, FormSectionInstanceId, IsOther, Value, CreatedByUserId, CreatedDate, UpdatedByUserId, UpdatedDate)
SELECT
#NewFormHeaderId, FormFieldId, fsit.NewFormSectionInstanceId, IsOther, Value, #UserId, CreatedDate, #UserId, UpdatedDate
FROM [dbo].[FormDetail] fd
INNER JOIN #FormSectionInstanceTable fsit ON fsit.OldFormSectionInstanceId = fd.FormSectionInstanceId
WHERE [FormHeaderId] = #FormHeaderId
Here's a solution that doesn't use MERGE (which I've had problems with many times I try to avoid if possible). It relies on two memory tables (you could use temp tables if you want) with IDENTITY columns that get matched, and importantly, using ORDER BY when doing the INSERT, and WHERE conditions that match between the two INSERTs... the first one holds the source IDs and the second one holds the target IDs.
-- Setup... We have a table that we need to know the old IDs and new IDs after copying.
-- We want to copy all of DocID=1
DECLARE #newDocID int = 99;
DECLARE #tbl table (RuleID int PRIMARY KEY NOT NULL IDENTITY(1, 1), DocID int, Val varchar(100));
INSERT INTO #tbl (DocID, Val) VALUES (1, 'RuleA-2'), (1, 'RuleA-1'), (2, 'RuleB-1'), (2, 'RuleB-2'), (3, 'RuleC-1'), (1, 'RuleA-3')
-- Create a break in IDENTITY values.. just to simulate more realistic data
INSERT INTO #tbl (Val) VALUES ('DeleteMe'), ('DeleteMe');
DELETE FROM #tbl WHERE Val = 'DeleteMe';
INSERT INTO #tbl (DocID, Val) VALUES (6, 'RuleE'), (7, 'RuleF');
SELECT * FROM #tbl t;
-- Declare TWO temp tables each with an IDENTITY - one will hold the RuleID of the items we are copying, other will hold the RuleID that we create
DECLARE #input table (RID int IDENTITY(1, 1), SourceRuleID int NOT NULL, Val varchar(100));
DECLARE #output table (RID int IDENTITY(1,1), TargetRuleID int NOT NULL, Val varchar(100));
-- Capture the IDs of the rows we will be copying by inserting them into the #input table
-- Important - we must specify the sort order - best thing is to use the IDENTITY of the source table (t.RuleID) that we are copying
INSERT INTO #input (SourceRuleID, Val) SELECT t.RuleID, t.Val FROM #tbl t WHERE t.DocID = 1 ORDER BY t.RuleID;
-- Copy the rows, and use the OUTPUT clause to capture the IDs of the inserted rows.
-- Important - we must use the same WHERE and ORDER BY clauses as above
INSERT INTO #tbl (DocID, Val)
OUTPUT Inserted.RuleID, Inserted.Val INTO #output(TargetRuleID, Val)
SELECT #newDocID, t.Val FROM #tbl t
WHERE t.DocID = 1
ORDER BY t.RuleID;
-- Now #input and #output should have the same # of rows, and the order of both inserts was the same, so the IDENTITY columns (RID) can be matched
-- Use this as the map from old-to-new when you are copying sub-table rows
-- Technically, #input and #output don't even need the 'Val' columns, just RID and RuleID - they were included here to prove that the rules matched
SELECT i.*, o.* FROM #output o
INNER JOIN #input i ON i.RID = o.RID
-- Confirm the matching worked
SELECT * FROM #tbl t