A requirement arises in many systems to update multiple SQL database rows.For small numbers of rows requiring updates, it can be adequate to use an UPDATE statement for each row that requires an update.I'll just call it using an aliased subselect as that makes more sense in my mind. One last thing before the example that you'll want to pay close attention to.
This was what I used to update 1 of the records, I'm using Oracle SQL: Cloyd, the description is indeed confusing. Please, shall you consider this worth, comment out and I'll keep editing the answer until we get 'there'.
For multiple-table updates, there is no guarantee that assignments are carried out in any particular order. COLUMN2 IS NULLAn outerjoin is performed based on the equijoin condition.
If you set a column to the value it currently has, My SQL notices this and does not update it. Records not matching the equijoin from table2 are marked with null.
To fix it, we run the following SQL statement: IMPORTANT: When using the UPDATE statement, pay special attention to make sure that some type of filtering criteria is specified. UPDATE Store_Information SET Sales = 800 WHERE Store_Name = 'Boston'; 2. What is the content of the table after the following SQL statement is executed?
UPDATE Store_Information SET Sales = 2000 WHERE Store_Name = 'Los Angeles' AND Txn_Date = 'Jan-10-1999'; 3. What is the content of the table after the following SQL statement is executed?
create table Employee( 2 ID VARCHAR2(4 BYTE) NOT NULL, 3 First_Name VARCHAR2(10 BYTE), 4 Last_Name VARCHAR2(10 BYTE), 5 Start_Date DATE, 6 End_Date DATE, 7 Salary Number(8,2), 8 City VARCHAR2(10 BYTE), 9 Description VARCHAR2(15 BYTE) 10 ) 11 / Table created.