Updating a select statement to update updating 1st gen ipod touch

Personally, if it wasn't for the 0.001% of the time where there's no other solution, I don't even think it should even be an available function in T-SQL.T-SQL is designed to be set-based, so it works on entire sets of data as a whole; it should NOT be used to work on data line-by-line.You can use the WHERE clause with the UPDATE query to update the selected rows, otherwise all the rows would be affected.The basic syntax of the UPDATE query with a WHERE clause is as follows − ---- ---------- ----- ----------- ---------- | ID | NAME | AGE | ADDRESS | SALARY | ---- ---------- ----- ----------- ---------- | 1 | Ramesh | 32 | Ahmedabad | 2000.00 | | 2 | Khilan | 25 | Delhi | 1500.00 | | 3 | kaushik | 23 | Kota | 2000.00 | | 4 | Chaitali | 25 | Mumbai | 6500.00 | | 5 | Hardik | 27 | Bhopal | 8500.00 | | 6 | Komal | 22 | MP | 4500.00 | | 7 | Muffy | 24 | Indore | 10000.00 | ---- ---------- ----- ----------- ---------- ---- ---------- ----- ----------- ---------- | ID | NAME | AGE | ADDRESS | SALARY | ---- ---------- ----- ----------- ---------- | 1 | Ramesh | 32 | Ahmedabad | 2000.00 | | 2 | Khilan | 25 | Delhi | 1500.00 | | 3 | kaushik | 23 | Kota | 2000.00 | | 4 | Chaitali | 25 | Mumbai | 6500.00 | | 5 | Hardik | 27 | Bhopal | 8500.00 | | 6 | Komal | 22 | Pune | 4500.00 | | 7 | Muffy | 24 | Indore | 10000.00 | ---- ---------- ----- ----------- ---------- If you want to modify all the ADDRESS and the SALARY column values in the CUSTOMERS table, you do not need to use the WHERE clause as the UPDATE query would be enough as shown in the following code block. This means that you have to select on all the fields which comprise a unique key -- a non-unique primary key is not sufficient.Without uniqueness, you are reduced to something like @Paul Karr's loop -- and if there is not a unique correlation, then more than one target row may be updated for each source row.

The SQL UPDATE Query is used to modify the existing records in a table.

Compound assignment operator: = Add and assign -= Subtract and assign *= Multiply and assign /= Divide and assign %= Modulo and assign &= Bitwise AND and assign ^= Bitwise XOR and assign |= Bitwise OR and assign Returns updated data or expressions based on it as part of the UPDATE operation. 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.

The OUTPUT clause is not supported in any DML statements that target remote tables or views. 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. 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.

Firstly: if the subselect was returning multiple values, then the for loop will be overwriting the name on table2 multiple times for some/all records (not clean). Assuming the outcome of the for loop was intended, the original subselect could have been rewritten in some controlled way to return only 1 value for each record...

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Secondly: there is no order by clause so this will occur in an unpredictable manner (i.e. simplest contrived way would be (select min(name)...)Long story short: if you can at all avoid it, never ever EVER use any kind of LOOP in a T-SQL statement.

Second, the SET clause specifies which column that you want to modify and the new values.

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