I want to update every row in my table from upper case to lower case. I searched everywhere but could not found relevant answer. I dont want it to select using SELECT. I would like to alter permanently may be using ALTER.
I am using SQL server 2008.
Thanks.
UPDATE table_name SET col1 = LOWER(col1), col2 = LOWER(col2), col3 = LOWER(col3);
HTH
Edit: Updating multiple columns. Just keep on adding columns like above. There is no direct automated way to update all the columns with a single command. Well, technically it may be possible using cursors, but I would advise against it since this looks like a one time process and you are better off with writing a command once and for all.
You can do this using string functions:
UPDATE MyTable SET MyColumn = LOWER(MyColumn)
There's the LOWER function. You'll need to UPDATE your table:
UPDATE mytable SET charfld1=LOWER(charfld1), charfld2=LOWER(charfld2), ...
Put all your textual fields after the SET.
Related
I'm new to SQL Server and am doing some cleanup of our transaction database. However, to accomplish the last step, I need to update a column in one table of one database with the value from another column in another table from another database.
I found a SQL update code snippet and re-wrote it for our own needs but would love someone to give it a once over before I hit the execute button since the update will literally affect hundreds of thousands of entries.
So here are the two databases:
Database 1: Movement
Table 1: ItemMovement
Column 1: LongDescription (datatype: text / up to 40 char)
Database 2: Item
Table 2: ItemRecord
Column 2: Description (datatype: text / up to 20 char)
Goal: set Column1 from db1 to the value of Colum2 from db2.
Here is the code snippet:
update table1
set table1.longdescription = table2.description
from movement..itemmovement as table1
inner join item..itemrecord as table2 on table1.itemcode = table2.itemcode
where table1.longdescription <> table2.description
I added the last "where" line to prevent SQL from updating the column where it already matches the source table.
This should execute faster and just update the columns that have garbage. But as it stands, does this look like it will run? And lastly, is it a straightforward process, using SQL Server 2005 Express to just backup the entire Movement db before I execute? And if it messes up, just restore it?
Alternatively, is it even necessary to re-cast the tables as table1 and table 2? Is it valid to execute a SQL query like this:
update movement..itemmovement
set itemmovement.longdescription = itemrecord.description
from movement..itemmovement
inner join item..itemrecord on itemmovement.itemcode = itemrecord.itemcode
where itemmovement.longdescription <> itemrecord.description
Many thanks in advance!
You don't necessarily need to alias your tables but I recommend you do for faster typing and reduce the chances of making a typo.
update m
set m.longdescription = i.description
from movement..itemmovement as m
inner join item..itemrecord as i on m.itemcode = i.itemcode
where m.longdescription <> i.description
In the above query I have shortened the alias using m for itemmovement and i for itemrecord.
When a large number of records are to be updated and there's question whether it would succeed or not, always make a copy in a test database (residing on a test server) and try it out over there. In this case, one of the safest bet would be to create a new field first and call it longdescription_text. You can make it with SQL Server Management Studio Express (SSMS) or using the command below:
use movement;
alter table itemmovement add column longdescription_test varchar(100);
The syntax here says alter table itemmovement and add a new column called longdescription_test with datatype of varchar(100). If you create a new column using SSMS, in the background, SSMS will run the same alter table statement to create a new column.
You can then execute
update m
set m.longdescription_test = i.description
from movement..itemmovement as m
inner join item..itemrecord as i on m.itemcode = i.itemcode
where m.longdescription <> i.description
Check data in longdescription_test randomly. You can actually do a spot check faster by running:
select * from movement..itemmovement
where longdescription <> longdescription_test
and longdescription_test is not null
If information in longdescription_test looks good, you can change your update statement to set m.longdescription = i.description and run the query again.
It is easier to just create a copy of your itemmovement table before you do the update. To make a copy, you can just do:
use movement;
select * into itemmovement_backup from itemmovement;
If update does not succeed as desired, you can truncate itemmovement and copy data back from itemmovement_backup.
Zedfoxus provided a GREAT explanation on this and I appreciate it. It is excellent reference for next time around. After reading over some syntax examples, I was confident enough in being able to run the second SQL update query that I have in my OP. Luckily, the data here is not necessarily "live" so at low risk to damage anything, even during operating hours. Given the nature of the data, the updated executed perfectly, updating all 345,000 entries!
I am going round in circles with a bit of SQL and would appreciate some help.
I've looked up creating temp tables, nested Select statements (where advice seems to be to avoid these like the plague) and various uses of Case statements but I can't seem to find a solution that works. I'd say I'm beginner level for SQL.
I have a table with 10 relevant records. The query that works to return all the relevant entries in the table is:
SELECT
TblServAct.ServActId
,TblServAct.ServActName
FROM TblServAct
WHERE TblServAct.ServActExclude IS NULL
ORDER BY TblServAct.ServActName
Here is where I run into problems:
When the parameter (#YESNOActivity) = Yes, I want all the rows in the table to be returned. I have managed to do this with a CASE statement
...however when the parameter (#YESNOActivity) = No, I want ONLY ONE row to be returned which doesn't actually exist in the table (and should not be inserted into the actual table). The values that I need to insert are: ServActId = 101 and ServActName = 'Select YES in Parameter2 to filter by Service Activity'
For background, the reason I am doing this is because I have found SSRS report parameters to be especially difficult to conditionally format. I want to use the dataset above to return a message in a parameter (lets call it parameter2) that the user needs to select yes in (#YESNOActivity) in order to see the full selection list in parameter2.
If I can get this to work I can see lots of potential for re-use so all advice appreciated
Thanks
Eileen
I believe this should do the job, just include your parameter in the WHERE clause and UNION it with your own row of data.
SELECT
TblServAct.ServActId
,TblServAct.ServActName
FROM TblServAct
WHERE TblServAct.ServActExclude IS NULL
AND #YESNOActivity = 'Yes'
UNION ALL
SELECT
ServActId = 101
,ServActName = 'Select YES in Parameter2 to filter by Service Activity'
WHERE #YESNOActivity = 'No'
ORDER BY TblServAct.ServActName
One way is to use this query:
SELECT
TblServAct.ServActId
,TblServAct.ServActName
FROM TblServAct
WHERE TblServAct.ServActExclude IS NULL
AND 'Yes' = #YESNOActivity
UNION ALL
SELECT
101 AS ServActId
,'Select YES in Parameter2 to filter by Service Activity' AS ServActName
WHERE 'No' = #YESNOActivity
ORDER BY TblServAct.ServActName
Another way would be to create two data flows and use your variable in a constraint to send the processing to one or the other.
A third way would be to put an expression on the SQL command and use your variable to switch between two SQL statements.
I'm still in the process of getting to fully understand SQL Server. I have wrote a stored procedure as shown below:
ALTER PROC [dbo].[Specific_Street_Lookup]
#STR Varchar(50),
#CNT int
AS
BEGIN
SELECT DISTINCT TOP (#CNT)
street_desc, street_localitydesc, postcode_selected
FROM
Full_Streets
INNER JOIN
Postcodes ON Full_Streets.street_postcodeid = postcodes.postcode_id
WHERE
street_desc LIKE #STR+'%'
AND postcode_selected = 'TRUE'
ORDER BY
street_desc, street_localitydesc
END
but it can take up to 7 seconds to return a result, I'm not sure what I can do to speed up the query.
The full_street table has a row count of 856800
The postcode table has a row count of 856208
Both tables have a primary key (street_id & postcode_id)
The purpose of the query: in my VB.net app as the user is typing in a street to look up it return a number of records (#CNT) that match the partial string (LIKE #STR'+%') and only if postcode_selected = 'TRUE'
I'm sure there must be a quicker / better way to do this and any help would be appreciated.
Thanks
Can you try with this index?
CREATE INDEX NCI_street_desc ON Full_Streets(street_desc) INCLUDE(street_localitydesc)
The LIKE operator is evil in such a big table, and I don't think you can optimize this query with normal indexes.
Consider using Full Text Search functionalities. With full text search you can't search portions of strings (unless you make a special table where you pre-save all the possible portions of your strings) but performance are hugely superior than what you can achieve using the LIKE operator.
I would change postcode_selected column type to bit (TRUE = 1, FALSE = 0) and then modify sp accordingly - it will reduce time complexity of the query.
I have a requirement to update a column with multiple values. The query looks like below.
Update table1 set column1 = (
select value from table2 where table1.column0 = table2.coulmn
)
Is there any generalised stored procedure for a requirement like the above?
short of creating a statement as a string and using the "execute" statement, I don't know of one. Generally "execute" is frowned on as it's a potential injection attack point.
Why would you want to update one table with information that is easily available in another? Seems like you are just guaranteeing that you are going to have to run this query every single time you perform an update, insert or delete against the camsnav table. Otherwise how are you going to keep them in sync?
Also, if you cannot guarantee that the sub-query will return exactly one row, it is probably safer to use the SQL Server-specific and proprietary update format:
UPDATE f SET nav = n.nav
FROM camsfolio AS f
INNER JOIN camsnav AS n
ON f.schcode = n.schcode;
SQL Server doesn't use "generalised stored procedures" for this kind of thing. It's up to you to build your own SP, composed using an appropriate parameterized UPDATE statement.
I'm still fairly new to T-SQL and SQL 2005. I need to import a column of integers from a table in database1 to a identical table (only missing the column I need) in database2. Both are sql 2005 databases. I've tried the built in import command in Server Management Studio but it's forcing me to copy the entire table. This causes errors due to constraints and 'read-only' columns (whatever 'read-only' means in sql2005). I just want to grab a single column and copy it to a table.
There must be a simple way of doing this. Something like:
INSERT INTO database1.myTable columnINeed
SELECT columnINeed from database2.myTable
Inserting won't do it since it'll attempt to insert new rows at the end of the table. What it sounds like your trying to do is add a column to the end of existing rows.
I'm not sure if the syntax is exactly right but, if I understood you then this will do what you're after.
Create the column allowing nulls in database2.
Perform an update:
UPDATE database2.dbo.tablename
SET database2.dbo.tablename.colname = database1.dbo.tablename.colname
FROM database2.dbo.tablename INNER JOIN database1.dbo.tablename ON database2.dbo.tablename.keycol = database1.dbo.tablename.keycol
There is a simple way very much like this as long as both databases are on the same server. The fully qualified name is dbname.owner.table - normally the owner is dbo and there is a shortcut for ".dbo." which is "..", so...
INSERT INTO Datbase1..MyTable
(ColumnList)
SELECT FieldsIWant
FROM Database2..MyTable
first create the column if it doesn't exist:
ALTER TABLE database2..targetTable
ADD targetColumn int null -- or whatever column definition is needed
and since you're using Sql Server 2005 you can use the new MERGE statement.
The MERGE statement has the advantage of being able to treat all situations in one statement like missing rows from source (can do inserts), missing rows from destination (can do deletes), matching rows (can do updates), and everything is done atomically in a single transaction. Example:
MERGE database2..targetTable AS t
USING (SELECT sourceColumn FROM sourceDatabase1..sourceTable) as s
ON t.PrimaryKeyCol = s.PrimaryKeyCol -- or whatever the match should be bassed on
WHEN MATCHED THEN
UPDATE SET t.targetColumn = s.sourceColumn
WHEN NOT MATCHED THEN
INSERT (targetColumn, [other columns ...]) VALUES (s.sourceColumn, [other values ..])
The MERGE statement was introduced to solve cases like yours and I recommend using it, it's much more powerful than solutions using multiple sql batch statements that basically accomplish the same thing MERGE does in one statement without the added complexity.
You could also use a cursor. Assuming you want to iterate all the records in the first table and populate the second table with new rows then something like this would be the way to go:
DECLARE #FirstField nvarchar(100)
DECLARE ACursor CURSOR FOR
SELECT FirstField FROM FirstTable
OPEN ACursor
FETCH NEXT FROM ACursor INTO #FirstField
WHILE ##FETCH_STATUS = 0
BEGIN
INSERT INTO SecondTable ( SecondField ) VALUES ( #FirstField )
FETCH NEXT FROM ACursor INTO #FirstField
END
CLOSE ACursor
DEALLOCATE ACursor
MERGE is only available in SQL 2008 NOT SQL 2005
insert into Test2.dbo.MyTable (MyValue) select MyValue from Test1.dbo.MyTable
This is assuming a great deal. First that the destination database is empty. Second that the other columns are nullable. You may need an update instead. To do that you will need to have a common key.