In my (well, by now, short) experience, I had to learn both client side and server side technology, all on demand.
If a frontend developer needs to create (or modify) a functionality in SQL, he has no time to read manuals, but only to have a glimpse on the topics related to the new functionality.
UPDATE can be used to modify one column at a time or multiple columns at a time.
The syntax for updating a single column is as follows: In this case, there is only one row that satisfies the condition in the WHERE clause.
Question: I want to update multiple rows in my table, and I need to understand how to update multiple columns.
I already know how to update multiple rows using my where clause, but I don't see how to update multiple columns.
This book includes scripts and tools to hypercharge Oracle 11g performance and you can buy it for 30% off directly from the publisher.
Update a set a.value1 = b.value2 from a join b on…but not (or similar): Update a, b set a.value1 = b.value2, b.value5 = ‘x’ from a join b on…you can use view with INSTEAD OF trigger: CREATE TABLE [dbo].[t1]( [id] [uniqueidentifier] NOT NULL, [First Name] [varchar](50) NULL) go CREATE TABLE [dbo].[t2]( [id] [uniqueidentifier] NOT NULL, [Last Name] [varchar](50) NULL) GOinsert into t1 values(’76CC1607-1DAE-4878-A549-26518696CEF8′,’Alexandr’)insert into t2 values(’76CC1607-1DAE-4878-A549-26518696CEF8′,’Pechenko’)gocreate VIEW dbo.v1 with schemabinding as select dbo.t1.id, dbo.t1. Last Name from dbo.t1 join dbo.t2 on dbo.t2= dbo.t1CREATE TRIGGER tr_v1_upd ON dbo.v1 INSTEAD OF UPDATE ASUPDATE s SET s. First Name FROM dbo.t1 s JOIN inserted i ON = i.id; UPDATE s SET s. Last Name FROM dbo.t2 s JOIN inserted i ON = i.id;goupdate dbo.v1 set First Name = ‘FN’, Last Name = ‘LN’ where id = ’76CC1607-1DAE-4878-A549-26518696CEF8′goselect * from v1Pinal Dave is a SQL Server Performance Tuning Expert and an independent consultant.
If IGNORE is provided, all errors encountered during the update are ignored.
If an update on a row would result in a violation of a primary key or unique index, the update on that row is not performed.
If there are multiple rows that satisfy the condition, all of them will be modified.
If no WHERE clause is specified, all rows will be modified.