I have a scalar function that takes a two variables #input1 #input2 and it returns the value of #input1 and #input2 (actual thing is more complex but this distills the idea).
I want to update all rows in a table column using this function, passing the value 'abc ' for #input1 and using the column name in #input2, so my update statement would look something like:
update mytable set mycolumn = (select dbo.myfunc( 'abc ' , mycolumn ) )
-- prepend the literal 'abc ' to every row for column mycolumn
But this is of course not allowed.
I'm trying to perform some mass string handling on a couple of columns based on some string rules. All ideas appreciated.
Thanks.
UPDATE mytable
SET mycolumn = dbo.myfunc('abc', mycolumn)
Related
I need to make a update query that can allow me to update in trimming leading '0' in a particular column. I know I can write a select query like this to select trimmed value below:
SELECT TRIM(LEADING '0' FROM SkuCode) FROM MyTable WHERE Id=1;
But how can implement this is in update query. Please help me.
if the column is a text or varchar type try
UPDATE MyTable set SkuCode = SUBSTRING(SkuCode,2) WHERE Id = 1
If this SELECT statement is returning the value you want to assign to the skucode column:
SELECT t.skucode AS current_skucode
, TRIM(LEADING '0' FROM t.skucode) AS proposed_skucode
FROM MyTable t
WHERE t.id=1 ;
Then you can convert that into an UPDATE statement, by replacing SELECT ... FROM with UPDATE, and adding a SET clause before the WHERE clause, to assign the expression that returns the proposed value for sku code to the sku code column, e.g.
UPDATE MyTable t
SET t.skucode = TRIM(LEADING '0' FROM t.skucode)
WHERE t.id=1 ;
I am trying to remove name_ part of each name in database, name_ is mistakenly inserted into db and now in 30 object names. if i remove manuelly from db, it takes me much time.
one example is: name_john. it should be john.
how can i delete this name_ from all names of all objects in db with some sql statement?
If it are column values you can do it with an update statement.
UPDATE table_reference
SET column_reference = SUBSTRING(column_reference, 6)
WHERE column_reference LIKE 'name\_%' ESCAPE '\'
If this is about column values that you need to modify, you could use the REPLACE() function like this:
UPDATE tablename
SET columnname = REPLACE(columnname, 'name_', '')
WHERE columnname LIKE '%name\_%' ESCAPE '\'
;
That would remove all entries of name_ in columnname. If there can be no more than one entry (or if only one needs to be removed) and its position is fixed, you could use the INSERT() function instead, which, despite its name, can also replace and delete substrings. This is how you could use it if the position of name_ was e.g. at the beginning:
UPDATE tablename
SET columnname = INSERT(columnname, 1, 5, '')
WHERE columnname LIKE 'name\_%' ESCAPE '\'
;
Say, you got a table of 100 records. And field age contains a some integers. And you want all those integers to be incremented by 1.
or you got a textfield called name and a bunch of names in there. And you want all those names to be prefixed as Mr..
Is there a way to achieve this in one SQL command?
The alternative would be to compile a recordset of these 100 recs and going thru a loop and then running an individual update statement.
Use the update command
update yourtable
set age=age +1
update yourtable
set name = 'Mr. ' + name
where gender='M'
UPDATE mytable SET age = age+1
UPDATE mytable SET name = CONCAT('Mr. ', name)
If MySQL is in ANSI mode – specifically, PIPES_AS_CONCAT, you can use 'Mr. ' || name instead.
I have a database table in MYSQL with around 1000 rows. In the table I have a column called 'overview'. In each row, this column has some value and at the end of that value I have a specific line (text) starting with: 'Source...'
Now what I want is, I want to remove this line from each column and replace it with some other text content.
I believe it can be accomplished with some smart query.
You can simply use REPLACE in your query like this
UPDATE your_table SET col_name = REPLACE(col_name , ‘Source...’, ‘new_val’)
WHERE col_name LIKE '%Source...';
Check Out the SQLFIDDLE.
MySQL database has a handy and simple string function REPLACE() that allows table data with the matching string (from_string) to be replaced by new string (to_string).
The syntax of REPLACE is:
REPLACE (text_string, from_string, to_string)
In your case, you can do this way:
UPDATE `tableName` SET `column` = REPLACE(column , 'Source...', 'Replaced Value')
Use Replace
update TBL
set overview = Replace(picture, 'Source..', 'replacement')
keep a backup of the table before anything.Or you can do it on a copy.
you can do this by following:
update table_name set col_name = replace(column_name , ‘Source...’, ‘Replaced String...’);
I need a SQL update statement for updating a particular field of all the rows with a string "test" to be added in the front of the existing value.
For example, if the existing value is "try" it should become "testtry".
You can use the CONCAT function to do that:
UPDATE tbl SET col=CONCAT('test',col);
If you want to get cleverer and only update columns which don't already have test prepended, try
UPDATE tbl SET col=CONCAT('test',col)
WHERE col NOT LIKE 'test%';
UPDATE tablename SET fieldname = CONCAT("test", fieldname) [WHERE ...]
Many string update functions in MySQL seems to be working like this:
If one argument is null, then concatenation or other functions return null too.
So, to update a field with null value, first set it to a non-null value, such as ''
For example:
update table set field='' where field is null;
update table set field=concat(field,' append');
That's a simple one
UPDATE YourTable SET YourColumn = CONCAT('prependedString', YourColumn);
UPDATE table_name SET Column1 = CONCAT('newtring', table_name.Column1) where 1
UPDATE table_name SET Column1 = CONCAT('newtring', table_name.Column2) where 1
UPDATE table_name SET Column1 = CONCAT('newtring', table_name.Column2, 'newtring2') where 1
We can concat same column or also other column of the table.