How to give static value to newly inserted rows in SQL Server - sql-server

I have a table, while inserting new records into that table I want to specify new static value for all those records. That static value should be same for all those records, again while inserting some other records want to give another new static value automatically.
Id name salary staticid
-----------------------
1 xyx 100 sh0001
2 ddd 200 sh0001
3 dfs 250 sh0001
While inserting new records I need output like this
Id name salary staticid
------------------------
1 xyx 100 sh0001
2 ddd 200 sh0001
3 dfs 250 sh0001
4 dsaf 320 sh0002
5 wew 650 sh0002
6 ter 365 sh0002
Thanks,

Simplest thing to do would be to insert your static value as you are filling your data/table.
DECLARE #staticValue varchar(100)
SET #staticValue = 'sh0001'
--Static Value 1 / Inserts
INSERT INTO dbo.tblA
(Id, name, salary, staticid)
SELECT 1, 'xyx', 100, #staticValue
UNION SELECT 2, 'ddd', 200, #staticValue
UNION SELECT 3, 'dfs', 250, #staticValue
--Static Value 2 / Inserts
SET #staticValue = 'sh0002'
INSERT INTO dbo.tblA
(Id, name, salary, staticid)
SELECT 4, 'dsaf', 320, #staticValue
Another option, although it requires additional SQL Server permissions for DDL - Data Definition Language, would be to use a default constraint, as below
--Static Value 1 / Inserts
BEGIN TRANSACTION
GO
ALTER TABLE dbo.tblB ADD CONSTRAINT
DF_tblB_staticid DEFAULT 'sh0001' FOR staticid
GO
ALTER TABLE dbo.tblB SET (LOCK_ESCALATION = TABLE)
GO
COMMIT
INSERT INTO dbo.tblB
(Id, name, salary)
SELECT 1, 'xyx', 100
UNION SELECT 2, 'ddd', 200
UNION SELECT 3, 'dfs', 250
--Static Value 2 / Inserts
BEGIN TRANSACTION
GO
ALTER TABLE dbo.tblB
DROP CONSTRAINT DF_tblB_staticid --Removes 'sh0001' default
GO
ALTER TABLE dbo.tblB ADD CONSTRAINT
DF_tblB_staticid DEFAULT ('sh0002') FOR staticid
GO
ALTER TABLE dbo.tblB SET (LOCK_ESCALATION = TABLE)
GO
COMMIT
INSERT INTO dbo.tblB
(Id, name, salary)
SELECT 4, 'dsaf', 320

Related

How to compare two attributes from two different tables in a trigger?

So I have two tables:
CREATE TABLE SALE(
OID_PA NUMBER(*,0) PRIMARY KEY,
Amount INTEGER NOT NULL,
Delivery_DATE DATE NOT NULL,
OID_V NUMBER(*,0) NOT NULL,
CONSTRAINT "AMOUNTCHECK" CHECK(Amount >=0),
FOREIGN KEY (OID_V) REFERENCES TICKET(OID_V));
and
CREATE TABLE PRODUCT
( Code NUMBER(*,0) PRIMARY KEY,
Stock INTEGER NOT NULL,
Price NUMBER(4,2) NOT NULL,
Production_Cost NUMBER NOT NULL,
Model VARCHAR2(50) NOT NULL,
TipoMueble VARCHAR2(50) NOT NULL,
TipoMaterial VARCHAR2(50) NOT NULL,
OID_PA NUMBER(*,0) NOT NULL,
CONSTRAINT "TipoMueble" CHECK(TipoMueble IN
('Canteado','Complementos','Glaciar',
'GrupoDiseño','Tiradores','Vitrinas')),
CONSTRAINT "TipoMaterial" CHECK(TipoMaterial IN ('Aluminio','Lacados',
'Polilaminado','Madera','Cristal','Chapa','Granito','Formica',
'Aglomerado','Marmol','Elementos de ferreteria')),
CONSTRAINT "StockNegativo" CHECK(Stock >=0),
CONSTRAINT "Precio" CHECK(Price>=0),
CONSTRAINT "CosteProduccion" CHECK (Production_cost>=0),
FOREIGN KEY (OID_PA) REFERENCES PAQUETE(OID_PA));
And now I want to create a trigger, the moment I modify the attribute "Amount" in the table "SALE" then it should check the table "PRODUCT".
if "stock" (in PRODUCT) is less than Amount (in SALE) then
RAISE_APPLICATION_ERROR(-20003, 'Not enough stock');
But I don't know how to make the trigger check in both tables at the same time.
right now my code looks likethis right now, it also has some errors that I'm not sure how to fix.
CREATE OR REPLACE TRIGGER TR_ENOUGH_STOCK
AFTER INSERT OR UPDATE OF Amount ON SALE
BEGIN
SELECT a.Amount, b.Stock
FROM ( SALE a inner join PRODUCT b on (a.Code = b.Code))
IF b.Stock < a.Amount THEN
RAISE APPLICATION ERROR(-20003, 'Not enough stock');
END IF;
END;
/
And I'm getting the following errors:
Error(209,5): PL/SQL: SQL Statement ignored
Error(212,5): PL/SQL: ORA-00933: SQL command not properly ended
Error(214,9): PLS-00103: Encountered the symbol "IF" when expecting one of
the following: ; <an identifier> <a double-quoted delimited-identifier>
Here's an example of how you might do that.
Create tables & a trigger:
SQL> create table sale (oid_pa number, amount number);
Table created.
SQL> create table product (code number, stock number, oid_pa number);
Table created.
SQL>
SQL> create or replace trigger trg_biu_stock
2 before insert or update
3 on sale
4 for each row
5 declare
6 l_stock product.stock%type;
7 begin
8 select stock into l_stock
9 from product
10 where oid_pa = :new.oid_pa;
11
12 if :new.amount > l_stock then
13 raise_application_error(-20000, 'Not enough stock');
14 end if;
15 end;
16 /
Trigger created.
SQL>
Insert sample records into the PRODUCT table:
SQL> insert into product values (1, 100, 10);
1 row created.
SQL> insert into product values (2, 50, 20);
1 row created.
SQL> select * From product;
CODE STOCK OID_PA
---------- ---------- ----------
1 100 10
2 50 20
SQL>
Let's test it:
SQL> -- 90 is less OID_PA = 10 stock value (which is 100)
SQL> insert into sale values (10, 90);
1 row created.
SQL> -- let's try to update it to a value larger than stock value:
SQL> update sale set amount = 200 where oid_pa = 10;
update sale set amount = 200 where oid_pa = 10
*
ERROR at line 1:
ORA-20000: Not enough stock
ORA-06512: at "HR.TRG_BIU_STOCK", line 9
ORA-04088: error during execution of trigger 'HR.TRG_BIU_STOCK'
SQL> -- how about a value which doesn't exceed the stock value?
SQL> update sale set amount = 5 where oid_pa = 10;
1 row updated.
SQL> select * From sale;
OID_PA AMOUNT
---------- ----------
10 5
SQL>
As of your attempt: apart from trigger code having wrong syntax, it wouldn't work anyway because you can't reference a table trigger is based on because it is right now being changed, i.e. it is mutating. Oracle raises an error in such cases (see an example below). The correct way is to reference that table's columns using :new or :old, as I did (see an example above).
SQL> create or replace trigger trg_biu_stock
2 before insert or update
3 on sale
4 for each row
5 declare
6 l_stock product.stock%type;
7 begin
8 select p.stock into l_stock
9 from product p
10 join sale s
11 on s.oid_pa = p.oid_pa
12 where p.oid_pa = :new.oid_pa;
13
14 if :new.amount > l_stock then
15 raise_application_error(-20000, 'Not enough stock');
16 end if;
17 end;
18 /
Trigger created.
SQL> update sale set amount = 50 where oid_pa = 10;
update sale set amount = 50 where oid_pa = 10
*
ERROR at line 1:
ORA-04091: table HR.SALE is mutating, trigger/function may not see it
ORA-06512: at "HR.TRG_BIU_STOCK", line 4
ORA-04088: error during execution of trigger 'HR.TRG_BIU_STOCK'
SQL>

Unique values in two columns

I have two columns and I need them both to be unique between each other (like it is 1 column).
My first attempt was to create sequence and set default constraints.
create sequence seq1
as bigint
start with 1
increment by 1
cache;
go
create table product (
pk uniqueidentifier
, id_1 bigint not null default (next value for seq1)
, id_2 bigint not null default (next value for seq1)
);
go
insert into product (pk) values (newid());
insert into product (pk) values (newid());
insert into product (pk) values (newid());
insert into product (pk) values (newid());
insert into product (pk) values (newid());
go
And it doesn't work. The result of query above will be:
id_1 id_2
1 1
2 2
3 3
4 4
5 5
Currently I stopped using 2 sequences with even and not even numbers.
create sequence seq2
as bigint
start with 1
increment by 2
cache;
go
create sequence seq3
as bigint
start with 2
increment by 2
cache;
go
But if in future I will need to add another column which also must be unique I will have a problem.
I also thinked about stored procedures. Something like this works for me.
create procedure sp_insertProduct
as
begin
declare #id1 as bigint = next value for seq1;
declare #id2 as bigint = next value for seq1;
insert into product (pk, id_1, id_2) values (newid(), #id1, #id2);
end
go
exec sp_insertProduct;
exec sp_insertProduct;
exec sp_insertProduct;
go
But due to my ORM framework restictions I cannot use stored procedures for inserting.
So is there a better solution for that problem?
PS. for some reasons I can not use uniqueidentifiers.
UPDATE
I think I need to explain question a bit clearly. I have a working solution for now (and both current answers will also work), but I wonder if there is a extensible solution to:
provide uniqueness of values in multiple columns (with ability to
add additional columns in future).
avoid using uniqueidentifiers
for better understanding of question, this is how I check uniqueness:
with src as (
select id_1 as id from product
union all
select id_2 as id from product
)
select id, count(*) as equal_values
from src
group by id
having (count(*) > 1)
create sequence seq1
as bigint
start with 1
increment by 2
cache;
go
create table product (
pk uniqueidentifier
, id_1 bigint not null default (next value for seq1)
, id_2 bigint not null default (next value for seq1 + 1)
);
go
doing this..
insert into product (pk) values (newid());
insert into product (pk) values (newid());
insert into product (pk) values (newid());
insert into product (pk) values (newid());
insert into product (pk) values (newid());
this would generate..
pk id_1 id_2
2A159914-8105-4DC1-9D7E-570CC5444172 1 2
6DAFEF16-2B81-4A10-99EF-B3F1A74389C6 3 4
8C6F6697-D993-4320-92BB-04CD56804C5A 5 6
AC97F37F-CAC3-4E83-BDD4-4B55D009C334 7 8
3DDAADA0-D7DB-4350-8087-ABF02B539552 9 10
SQL Fiddle
May be this seems very naive but it should work. I didn't check but you may need to add some parenthesis:
create table product (
pk uniqueidentifier
, id_1 bigint not null default (next value for seq1)
, id_2 bigint not null default (-next value for seq1)
);
go

How to batch insert multiple rows at once into a table with an auto incremented id field in oracle? [duplicate]

How do you do multiple insert with SQL in Oracle 12c when you have an identity column?
INSERT ALL
INTO Table1 (Column2) Values (1)
INTO Table1 (Column2) Values (2)
SELECT * FROM dual;
where Table1 has column1 as an identity, will set the identity column to have the same value which violates the primary key constraint.
CREATE TABLE Table1 (
Table1Id NUMBER GENERATED ALWAYS AS IDENTITY,
column2 VARCHAR2(255),
column3 NUMBER,
PRIMARY KEY (Table1Id)
);
INSERT ALL
INTO Table1 (column2, column3) VALUES ('a', '1')
INTO Table1 (column2, column3) VALUES ('b', '2')
SELECT * FROM dual;
--SQL Error: ORA-00001: unique constraint violated
What am I doing wrong with this?
EDIT Added two test cases, and a possible workaround.
Though Insert statement and insert all statement are practically the same conventional insert statement. But when it comes to sequences, they work differently.
Test case 1 : Identity columns
SQL> DROP TABLE table1 PURGE;
Table dropped.
SQL>
SQL> CREATE TABLE Table1 (
2 Table1Id NUMBER GENERATED ALWAYS AS IDENTITY,
3 column3 NUMBER,
4 PRIMARY KEY (Table1Id)
5 );
Table created.
SQL>
SQL> INSERT ALL
2 INTO Table1 (column3) VALUES ('1')
3 INTO Table1 (column3) VALUES ('2')
4 SELECT * FROM dual;
INSERT ALL
*
ERROR at line 1:
ORA-00001: unique constraint (LALIT.SYS_C0010439) violated
SQL>
Let's see what's actually happening under the hood -
SQL> CREATE TABLE Table1 (
2 Table1Id NUMBER GENERATED ALWAYS AS IDENTITY,
3 column3 NUMBER,
4 CONSTRAINT A UNIQUE (Table1Id)
5 );
Table created.
SQL> INSERT ALL
2 INTO Table1 (column3) VALUES (1)
3 INTO Table1 (column3) VALUES (2)
4 SELECT * FROM dual;
INSERT ALL
*
ERROR at line 1:
ORA-00001: unique constraint (LALIT.A) violated
SQL> SELECT * FROM table1;
no rows selected
SQL> ALTER TABLE table1
2 DISABLE CONSTRAINT a;
Table altered.
SQL> INSERT ALL
2 INTO Table1 (column3) VALUES (1)
3 INTO Table1 (column3) VALUES (2)
4 SELECT * FROM dual;
2 rows created.
SQL> SELECT * FROM table1;
TABLE1ID COLUMN3
---------- ----------
2 1
2 2
SQL>
So, the sequence progressed to nextval however there was an unique constraint violation the first time we did an Insert All. Next, we disabled the unique constraint, and the subsequent Insert All reveals that the sequence did not progress to nextval, rather it attempted to insert duplicate keys.
Though the issue doesn't occur with a INSERT-INTO-SELECT statement.
SQL> INSERT INTO table1(column3) SELECT LEVEL FROM dual CONNECT BY LEVEL <=5;
5 rows created.
SQL>
SQL> SELECT * FROM table1;
TABLE1ID COLUMN3
---------- ----------
2 1
3 2
4 3
5 4
6 5
SQL>
Surprisingly, as per the metadata, the sequence is supposed to proceed to nextval automatically, however it doesn't happen with an Insert All statement.
SQL> SELECT COLUMN_NAME,
2 IDENTITY_COLUMN,
3 DATA_DEFAULT
4 FROM user_tab_cols
5 WHERE table_name ='TABLE1'
6 AND IDENTITY_COLUMN='YES';
COLUMN_NAME IDENTITY_COLUMN DATA_DEFAULT
--------------- --------------- ------------------------------
TABLE1ID YES "LALIT"."ISEQ$$_94458".nextval
SQL>
Test Case 2 : Using a sequence explicitly
The INSERT ALL would work the same way whether an identity column is used or an explicit sequence is used.
SQL> DROP SEQUENCE s;
Sequence dropped.
SQL>
SQL> CREATE SEQUENCE s;
Sequence created.
SQL>
SQL> DROP TABLE t PURGE;
Table dropped.
SQL>
SQL> CREATE TABLE t (
2 ID NUMBER,
3 text VARCHAR2(50),
4 CONSTRAINT id_pk PRIMARY KEY (ID)
5 );
Table created.
SQL>
SQL> INSERT ALL
2 INTO t VALUES (s.nextval, 'a')
3 INTO t VALUES (s.nextval, 'b')
4 INTO t VALUES (s.nextval, 'c')
5 INTO t VALUES (s.nextval, 'd')
6 SELECT * FROM dual;
INSERT ALL
*
ERROR at line 1:
ORA-00001: unique constraint (LALIT.ID_PK) violated
SQL>
SQL> SELECT * FROM T;
no rows selected
SQL>
SQL> ALTER TABLE t
2 DISABLE CONSTRAINT id_pk;
Table altered.
SQL> INSERT ALL
2 INTO t VALUES (s.nextval, 'a')
3 INTO t VALUES (s.nextval, 'b')
4 INTO t VALUES (s.nextval, 'c')
5 INTO t VALUES (s.nextval, 'd')
6 SELECT * FROM dual;
4 rows created.
SQL> SELECT * FROM T;
ID TEXT
---------- ----------------------------------------
2 a
2 b
2 c
2 d
SQL>
Possible workaround - Using a ROW LEVEL trigger
SQL> CREATE OR REPLACE TRIGGER t_trg
2 BEFORE INSERT ON t
3 FOR EACH ROW
4 WHEN (new.id IS NULL)
5 BEGIN
6 SELECT s.NEXTVAL
7 INTO :new.id
8 FROM dual;
9 END;
10 /
Trigger created.
SQL> truncate table t;
Table truncated.
SQL> INSERT ALL
2 INTO t (text) VALUES ('a')
3 INTO t (text) VALUES ('b')
4 INTO t (text) VALUES ('c')
5 INTO t (text) VALUES ('d')
6 SELECT * FROM dual;
4 rows created.
SQL> SELECT * FROM t;
ID TEXT
---------- -------------------------
3 a
4 b
5 c
6 d
SQL>
Here's a workaround using the UNION ALL method instead of the INSERT ALL method. For some reason the data must be wrapped in a select * from (...) or it will generate the error ORA-01400: cannot insert NULL into ("JHELLER"."TABLE1"."TABLE1ID").
insert into table1(column2, column3)
select *
from
(
select 'a', '1' from dual union all
select 'b', '2' from dual
);

Selecting newest entries with different types

I'm designing table which will contain properties of some objects which will change over time.
CREATE TABLE [dbo].[ObjectProperties]
(
[Id] INT NOT NULL PRIMARY KEY IDENTITY,
[ObjectType] SMALLINT NOT NULL,
[Width] SMALLINT NOT NULL,
[Height] SMALLINT NOT NULL,
[Weight] SMALLINT NOT NULL
)
Let's say I have this ObjectTypes:
1 = Chair
2 = Table
And Data for this table:
INSERT INTO [dbo].[ObjectProperties] ([Id], [ObjectType], [Width], [Height], [Weight]) VALUES (1, 1, 50, 50, 1000)
INSERT INTO [dbo].[ObjectProperties] ([Id], [ObjectType], [Width], [Height], [Weight]) VALUES (2, 2, 80, 40, 500)
INSERT INTO [dbo].[ObjectProperties] ([Id], [ObjectType], [Width], [Height], [Weight]) VALUES (3, 1, 50, 50, 2000)
So, as you can see I had Chair object which Weight was 1000 then I changed weight to 2000. And I'm storing something like modification history of objects properties.
Now I want to select newest data from this table for each object. I know how to select newest data for each object one by one:
SELECT TOP 1 * FROM [ObjectProperties] WHERE ObjectType = 1 ORDER BY Id DESC
But what if I want to select few objects with one query? Like
SELECT ... * FROM [ObjectProperties] WHERE ObjectType IN (1, 2) ...
And receive rows with ids 2 and 3 (because 3 has newer properties for Chair than 1)
You can use a CTE with ROW_NUMBER ranking function:
WITH CTE AS(
SELECT *,
RN=ROW_NUMBER()OVER(PARTITION BY ObjectType ORDER BY ID DESC)
FROM [ObjectProperties] op
)
SELECT * FROM CTE WHERE RN = 1
AND ObjectType IN (1, 2)
Demo
The ROW_NUMBER returns one row for every ObjectType-group order by ID DESC(so the record with the highest ID) .If you want to filter by certain ID's you just have to apply the appropriate WHERE clause, either in the CTE or in the outer SELECT.
Ranking Functions
A simple (admittedly crude) way is as follows:
select * from ObjectProperties where id in
(select max(id) from ObjectProperties group by objecttype)
This gives:
Id ObjectType Width Height Weight
----------- ---------- ------ ------ ------
2 2 80 40 500
3 1 50 50 2000

Auto running number ID with format xxxx/year number (9999/12) in SQL Server stored procedure

I have one table (Stock_ID, Stock_Name). I want to write a stored procedure in SQL Server with Stock_ID running number with a format like xxxx/12 (xxxx = number start from 0001 to 9999; 12 is the last 2 digits of current year).
My scenario is that if the year change, the running number will be reset to 0001/13.
what do you intend to do when you hit more than 9999 in a single year??? it may sound impossible, but I've had to deal with so many "it will never happen" data related design mess-ups over the years from code first design later developers. These are major pains depending on how may places you need to fix these items which are usually primary key and foreign keys used all over.
This looks like a system requirement to SHOW the data this way, but it is the developers responsibility to design the internals of the application. The way you store it and display it don't need to be identical. I'd split that into two columns, using an int for the number portion and a tiny int for the 2 digit year portion. You can use a computed column for quick and easy display (persist it and index if necessary), where you pad with leading zeros and add the slash. Throw in a check constraint on the year portion to make sure it stays within a reasonable range. You can make the number portion an identity and just have a job reseed it back to 1 every new years eve.
try it out:
--drop table YourTable
--create the basic table
CREATE TABLE YourTable
(YourNumber int identity(1,1) not null
,YourYear tinyint not null
,YourData varchar(10)
,CHECK (YourYear>=12 and YourYear<=25) --optional check constraint
)
--add the persisted computed column
ALTER TABLE YourTable ADD YourFormattedNumber AS ISNULL(RIGHT('0000'+CONVERT(varchar(10),YourNumber),4)+'/'+RIGHT(CONVERT(varchar(10),YourYear),2),'/') PERSISTED
--make the persisted computed column the primary key
ALTER TABLE YourTable ADD CONSTRAINT PK_YourTable PRIMARY KEY CLUSTERED (YourFormattedNumber)
sample data:
--insert rows in 2012
insert into YourTable values (12,'aaaa')
insert into YourTable values (12,'bbbb')
insert into YourTable values (12,'cccc')
--new years eve job run this
DBCC CHECKIDENT (YourTable, RESEED, 0)
--insert rows in 2013
insert into YourTable values (13,'aaaa')
insert into YourTable values (13,'bbbb')
select * from YourTable order by YourYear,YourNumber
OUTPUT:
YourNumber YourYear YourData YourFormattedNumber
----------- -------- ---------- -------------------
1 12 aaaa 0001/12
2 12 bbbb 0002/12
3 12 cccc 0003/12
1 13 aaaa 0001/13
2 13 bbbb 0002/13
(5 row(s) affected)
to handle the possibility of more than 9999 rows per year try a different computed column calculation:
CREATE TABLE YourTable
(YourNumber int identity(9998,1) not null --<<<notice the identity starting point, so it hits 9999 quicker for this simple test
,YourYear tinyint not null
,YourData varchar(10)
)
--handles more than 9999 values per year
ALTER TABLE YourTable ADD YourFormattedNumber AS ISNULL(RIGHT(REPLICATE('0',CASE WHEN LEN(CONVERT(varchar(10),YourNumber))<4 THEN 4 ELSE 1 END)+CONVERT(varchar(10),YourNumber),CASE WHEN LEN(CONVERT(varchar(10),YourNumber))<4 THEN 4 ELSE LEN(CONVERT(varchar(10),YourNumber)) END)+'/'+RIGHT(CONVERT(varchar(10),YourYear),2),'/') PERSISTED
ALTER TABLE YourTable ADD CONSTRAINT PK_YourTable PRIMARY KEY CLUSTERED (YourFormattedNumber)
sample data:
insert into YourTable values (12,'aaaa')
insert into YourTable values (12,'bbbb')
insert into YourTable values (12,'cccc')
DBCC CHECKIDENT (YourTable, RESEED, 0) --new years eve job run this
insert into YourTable values (13,'aaaa')
insert into YourTable values (13,'bbbb')
select * from YourTable order by YourYear,YourNumber
OUTPUT:
YourNumber YourYear YourData YourFormattedNumber
----------- -------- ---------- --------------------
9998 12 aaaa 9998/12
9999 12 bbbb 9999/12
10000 12 cccc 10000/12
1 13 aaaa 0001/13
2 13 bbbb 0002/13
(5 row(s) affected)
This might help:
DECLARE #tbl TABLE(Stock_ID INT,Stock_Name VARCHAR(100))
INSERT INTO #tbl
SELECT 1,'Test'
UNION ALL
SELECT 2,'Test2'
DECLARE #ShortDate VARCHAR(2)=RIGHT(CAST(YEAR(GETDATE()) AS VARCHAR(4)),2)
;WITH CTE AS
(
SELECT
CAST(ROW_NUMBER() OVER(ORDER BY tbl.Stock_ID) AS VARCHAR(4)) AS RowNbr,
tbl.Stock_ID,
tbl.Stock_Name
FROM
#tbl AS tbl
)
SELECT
REPLICATE('0', 4-LEN(RowNbr))+CTE.RowNbr+'/'+#ShortDate AS YourColumn,
CTE.Stock_ID,
CTE.Stock_Name
FROM
CTE
From memory, this is a way to get the next id:
declare #maxid int
select #maxid = 0
-- if it does not have #maxid will be 0, if it was it will give the next id
select #maxid = max(convert(int, substring(Stock_Id, 1, 4))) + 1
from table
where substring(Stock_Id, 6, 2) = substring(YEAR(getdate()), 3, 2)
declare #nextid varchar(7)
select #nextid = right('0000'+ convert(varchar,#maxid),4)) + '/' + substring(YEAR(getdate()), 3, 2)

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