Sql updating table from another table

Rated 3.98/5 based on 529 customer reviews

FROM Specifies that a table, view, or derived table source is used to provide the criteria for the update operation. If the object being updated is the same as the object in the FROM clause and there is only one reference to the object in the FROM clause, an object alias may or may not be specified.

If the object being updated appears more than one time in the FROM clause, one, and only one, reference to the object must not specify a table alias.

CURRENT OF Specifies that the update is performed at the current position of the specified cursor. Table1', ' U') IS NOT NULL DROP TABLE dbo. Table2', ' U') IS NOT NULL DROP TABLE dbo. Table1 (c1 int PRIMARY KEY NOT NULL, c2 int NOT NULL); GO CREATE TABLE dbo. Table2 WHERE CURRENT OF abc; GO SELECT c1, c2 FROM dbo.

A positioned update using a WHERE CURRENT OF clause updates the single row at the current position of the cursor. Table2 (d1 int PRIMARY KEY NOT NULL, d2 int NOT NULL); GO INSERT INTO dbo. Table2 VALUES (1, 20), (2, 30); GO DECLARE abc CURSOR LOCAL FOR SELECT c1, c2 FROM dbo. Table1; GO Support for use of the READUNCOMMITTED and NOLOCK hints in the FROM clause that apply to the target table of an UPDATE or DELETE statement will be removed in a future version of SQL Server.

If work correctly, but I am not sure how to write this as a SQL Statement SELECT dbo. Along with 16 years of hands on experience he holds a Masters of Science degree and a number of database certifications.

Col1 IN (21, 31) GOCan you help me with following TSQL. Shipment Method AS Update Value INTO #My Temp FROM dbo. He has authored 11 SQL Server database books, 21 Pluralsight courses and has written over 4000 articles on the database technology on his blog at a https://blog.

All other references to the object in the FROM clause must include an object alias.

sql updating table from another table-83

sql updating table from another table-30

sql updating table from another table-33

When you look at this it looks very simple but when we try to think the solution, I have seen developers coming up with many different solutions for example sometime they write cursor, table variables, local variables etc. Col2)) UPDATE CTE SET Col1 = _Col1, Col2 = _Col2from stackoverflow.“UPDATE Table1 SET Col2 = t2.

You can additionally use MERGE statement to do the same as well, however I personally prefer this method.

Let us clean up the clause by dropping the tables which we have created.performance wise I liked; (not my! guess you already covered it somewhere..; WITH CTE AS (SELECT T1.

This is one of the most interesting questions I keep on getting on this email and I find that not everyone knows about it. Our requirement is that we have Table2 which has two rows where Col1 is 21 and 31. Can you please let me know what are the cases multipart identifier error message will be shown.

In recent times I have seen a developer writing a cursor to update a table. We want to update the value from Table2 to Table1 for the rows where Col1 is 21 and 31. I resolved this by providing the alias name after update query:: UPDATE Table1 SET Col2 = t2.

Leave a Reply