Update multiple rows with different values in SQL - sql

I have a table like this:
SKU Size
A 10
B 10
C 10
D 10
E 10
F 10
G 10
I want to change it to:
SKU Size
A 20
B 10
C 30
D 10
E 80
F 10
G 60
I have more than 3000 rows of records to update. How can I do that with SQL update command ?

UPDATE T
SET Size = CASE SKU
WHEN 'A' THEN 20
WHEN 'B' THEN 10
WHEN 'C' THEN 30
WHEN ...
END
Or there may be a formula for calculating the size, but you've failed to give it in your question (Or we may have to switch to a more complex CASE expression, but again, too little detail in the question).

Create a table with the mapping of SKU to new size; update the master table from that.
Many dialects of SQL have a notation for doing updates via joined tables. Some do not. This will work where there is no such notation:
CREATE TABLE SKU_Size_Map
(
SKU CHAR(16) NOT NULL,
Size INTEGER NOT NULL
);
...Populate this table with the SKU values to be set...
...You must have such a list...
UPDATE MasterTable
SET Size = (SELECT Size FROM SKU_Size_Map
WHERE MasterTable.SKU = SKU_Size_Map.Size)
WHERE SKU IN (SELECT SKU FROM SKU_Size_Map);
The main WHERE condition is need to avoid setting the size to null where there is no matching row.
You can probably also do it with a MERGE statement. But the key insight for any of these notations is that you need a table to do the mapping between SKU and size. You either need a table or you need an algorithm, and the sample data doesn't suggest an algorithm.

Make use of OpenXML to resolve your issue
example
declare #i int
exec sp_xml_preparedocument #i output,
'<mydata>
<test xmlID="3" xmlData="blah blah blah"/>
<test xmlID="1" xmlData="blah"/>
</mydata>'
insert into test
select xmlID, xmlData
from OpenXml(#i, 'mydata/test')
with (xmlID int, xmlData nvarchar(30))
where xmlID not in (select xmlID from test)
update test
set test.xmlData = ox.xmlData
from OpenXml(#i, 'mydata/test')
with (xmlID int, xmlData nvarchar(30)) ox
where test.xmlID = ox.xmlID
exec sp_xml_removedocument #i

Just do...
UPDATE [yourTable] SET Size = 20 WHERE SKU = 'A'
And do this for all values you want to change...

Well, if you don't have a formula to calculate your Sizes, and you don't have a file or an Excel sheet with the data that you can massage into your table, you'll just have to get some luckless intern to type something like
UPDATE <table> SET Size = <value> WHERE SKU = '<key>'
3000 times.
If you are that intern, I'd suggest giving us a little more information...

Since you wanted to change the whole column, drop that particular column by using this:
ALTER TABLE table_name
DROP COLUMN column_name;
then create a new column using:
ALTER TABLE table_name
ADD column_name varchar(80);

Related

How to autocomplete SQL field based on same row fields

QUESTION HAS BEEN UPDATED:Let's say I have two tables:Table1
ID_Ticket | Ticket_Quantity | Total_Price(Calculated field)
--------------------------------------------
2 | 5 | x
1 | 3 | y
Table2
ID_Ticket | Ticket_Price
------------------------
1 | 4.5
2 | 5
I want to prevent the user of the database to fill the field of Total_Price (via Edit Top 200 Rows or queries), instead I want it to be calculated as Ticket_Price * Ticket_Quantity and be inserted automatically on that row. In this case, x should be 25 and y should be 13.5 (the values should be insterted automatically once Ticket_Quantity and Ticket_Price are filled for that row)I wrote a function like this:
CREATE FUNCTION Multiply(#x DECIMAL(19,4), #y DECIMAL (19,4))
RETURNS DECIMAL(19,4)
AS
BEGIN
SELECT #x * Ticket_Price
FROM Table2
WHERE ID_Ticket = #y
ENDBut there is an error:Select statements included within a function cannot return data to a client Also when I want to add the calculated field based on the function:ALTER TABLE Purchases
ADD Total_Price AS Multiply(Table2.Ticket_Price,Ticket_Quantity); The query doesn't execute and gives me this error:
The multi-part identifier "Product.Prod_Price" could not be bound.
How should I call the values from Table2 and fix the Multiply function?
I found a solution, so I'll post it for future readers who have the same problem:
In the Object Explorer (left panel) go to this path:
Databases --> <your_database_name> --> programmability --> functions
Right-click on the Functions folder and select New --> Scalar-valued function
Paste the following function script (replace < variables > with those that correspond to your database):
CREATE FUNCTION dbo.Multiply(#id INT, #price DECIMAL(19,4))
--or (#x float, #y money) depending on the type of your columns you have
RETURNS DECIMAL(19,4)
--RETURNS <data_type_of_the_calculated_column_you_want>
AS
BEGIN
RETURN
(SELECT #price * Ticket_Price
--SELECT #<second_argument/column_name_of_Table1>*<column_name_of_Table2>
FROM Table2
--FROM <your_Table2_name>
WHERE ID_Ticket = #id)
--WHERE <unique/PrimaryKey_Column_to_identify_the_row_in_Table2>
-- = #<ForeignKey_Column_to_identify_the_row_in_Table2>
END
And execute it.
Now Create a new query (Ctrl+N) to add the calculated column in Table1, and copy-paste the following query:
ALTER TABLE Table1
--ALTER TABLE <your_Table1_name>
ADD Total_Price AS dbo.Multiply(ID_Ticket,Ticket_Quantity);
--ADD <name_of_the_calculated_row_you_like> AS
-- dbo.<Function_Name>(<id_column_name_of_Table2>,<column_name_from_Table1>)
Execute the query.
Now the calculated column should be the multiplication of the columns of Table1 and Table2

Replace Any Occurrence of "P" in String With A Value From Another Table

I have a column, sort_order in a table that contains a string of numbers, a delimiter and some P values:
1150||P||1168||1144||1149||1147||1164||1152||P||1148||1162||1163||P||1156||1157||1154||
I would like to replace any P values in this string with another value from the event_tile_id column of another table.
So far I've drafted this SQL below with no luck. What changes can I make to this Query to get the effect I need?
`SELECT sort_order,
(
REPLACE(sort_order,'P',
(SELECT TOP 1 event_tile_id
FROM daily_email_sales_today)
)
)
as sort_order
FROM daily_email_preview`
Removed "default_SaleID" from Query. Replace should now have 4 arguments.
This is how I would do it.
Since you don't have any joins, why not do a simpler update query using a static value?
DECLARE #update VARCHAR(100)
SET #update = (SELECT TOP 1 event_tile_id FROM daily_email_sales_today)
update daily_email_preview
SET sort_order = replace(sort_order,'P', #update)
Or even,
update daily_email_preview
SET sort_order = replace(sort_order,'P', '<new value>')
Assuming you are using SQL Server.
Along the same thought process as #Eric_Hauenstein if you are running this in a TSQL process:
declare #rSTR as varchar(50)
SELECT TOP 1 #rSTR = event_tile_id FROM daily_email_sales_toda
SELECT sort_order, REPLACE(sort_order,'P', #rSTR) as sort_order
FROM daily_email_preview

comparable varchar "arrays" in seperate fields but on same row

I have a table that looks like this:
memberno(int)|member_mouth (varchar)|Inspected_Date (varchar)
-----------------------------------------------------------------------------
12 |'1;2;3;4;5;6;7' |'12-01-01;12-02-02;12-03-03' [7 members]
So by looking at how this table has been structured (poorly yes)
The values in the member_mouth field is a string that is delimited by a ";"
The values in the Inspected_Date field is a string that is delimited by a ";"
So - for each delimited value in member_mouth there is an equal inspected_date value delimited inside the string
This table has about 4Mil records, we have an application written in C# that normalizes the data and stores it in a separate table. The problem now is because of the size of the table it takes a long time for this to process. (the example above is nothing compared to the actual table, it's much larger and has a couple of those string "array" fields)
My question is this: What would be the best and fastest way to normilize this data in MSSQL proc? let MSSQL do the work and not a C# app?
The best way will be SQL itself. The way followed in the below code is something which worked for me well with 2-3 lakhs of data.
I am not sure about the below code when it comes to 4 Million, but may help.
Declare #table table
(memberno int, member_mouth varchar(100),Inspected_Date varchar(400))
Insert into #table Values
(12,'1;2;3;4;5;6;7','12-01-01;12-02-02;12-03-03;12-04-04;12-05-05;12-07-07;12-08-08'),
(14,'1','12-01-01'),
(19,'1;5;8;9;10;11;19','12-01-01;12-02-02;12-03-03;12-04-04;12-07-07;12-10-10;12-12-12')
Declare #tableDest table
(memberno int, member_mouth varchar(100),Inspected_Date varchar(400))
The table will be like.
Select * from #table
See the code from here.
------------------------------------------
Declare #max_len int,
#count int = 1
Set #max_len = (Select max(Len(member_mouth) - len(Replace(member_mouth,';','')) + 1)
From #table)
While #count <= #max_len
begin
Insert into #tableDest
Select memberno,
SUBSTRING(member_mouth,1,charindex(';',member_mouth)-1),
SUBSTRING(Inspected_Date,1,charindex(';',Inspected_Date)-1)
from #table
Where charindex(';',member_mouth) > 0
union
Select memberno,
member_mouth,
Inspected_Date
from #table
Where charindex(';',member_mouth) = 0
Delete from #table
Where charindex(';',member_mouth) = 0
Update #table
Set member_mouth = SUBSTRING(member_mouth,charindex(';',member_mouth)+1,len(member_mouth)),
Inspected_Date = SUBSTRING(Inspected_Date,charindex(';',Inspected_Date)+1,len(Inspected_Date))
Where charindex(';',member_mouth) > 0
Set #count = #count + 1
End
------------------------------------------
Select *
from #tableDest
Order By memberno
------------------------------------------
Result.
You can take a reference here.
Splitting delimited values in a SQL column into multiple rows
Do it on SQl server side, if possible a SSIS package would be great.

Assigning Value along with Data Retrieval

Is there a way to combine assigning a value to a variable and Selecting a column in sql. I need to compute and select a column in a table based on the variable. The variable's value changes based on another column in the table.
var #BeginValue
Columns in table : ReducedBy
My initial begin value is stored in #BeginValue. The table has reducedBy which is a factor by which my begin value should be reduced. So when i select, beginvalue for the first recored would be #BeginValue and the #EndValue should be #BeginValue = #BeginValue - reducedBy. It continues like this, as many times as the number of records in my table.
Result set must be like this:
#Begin = 10
Begin End ReducedBy
10 8 2
8 6 2
6 5 1
Is there a way with which i can achieve this without using a cursor or with multiple update statements.
You can't assign in a query that returns a result set. The closest you can get is to store the result in a table variable. Then you can both do computations against that table, and return it as a result set:
-- Store results in table variable
declare #tbl table (id int, col1 int, ...)
insert #tbl
(id, col1, ...)
select id
, col1
, ...
from ... your query here ...
-- Assign variable
select #YourVariable = ... your computation here ...
from #tbl
-- Return result set
select *
from #tbl
If your question is
Can I do..
SELECT #a = field, field2 from table
and get a resultset and set the value of #a?
Then the answer is no, not in a single statement.

SQL select multiple rows of data then compare

What would be the best approach in SQL Server 2008 to select something that can contain 10 list of data, then compare that data with a specific value in one of it's columns
So something like this below
SELECT bType FROM WORK_STATION WHERE nFileId = 123456789
Which could return either 1 - 10 values MAX (will return at least one value). Then to compare the data from that SQL statement above that we just selected to a specific value to something like
if bType = 1
--DO something
What is the best approach of doing something like this?
declare #table as table(btype int)
declare #btype int
insert into #table
SELECT bType FROM WORK_STATION WHERE nFileId = 123456789
while(exists(select top 1 'x' from #table)) --as long as #table contains records continue
begin
select top 1 #btype = btype from #table
if(#btype = 10)
print 'something'
delete top (1) from #table --remove the previously processed row. also ensures no infinite loop
end
I think you can use SP to declare variables and then compare it with the resultset, if you know that you have only 10 values you can use temp table and insert 10 values.
I hope this is helpful.