How To Add Record To A Field In A Table Oracle Using Update

Question: I need to run into how to update a table in Oracle. When updating a table in Oracle, what are the syntax options?

Reply: At that place are many o[options when updating Oracle, and you tin can update a Oracle table:

update mytab values (123, 'Fred');

update emp set sal = sal * ane.ane;

The Oracle UPDATE statement locates one or more rows (or all the rows) in a table and sets i or more columns to the specified values. As with the INSERT statement, the values must either match the columns information type or one that the database can implicitly convert. The bones format is:

update <table name> set (<col1 = val1, col2 = val2,col3 = val3,?) where <expression identifying rows to change>;

Allow's become back to the AUTHOR tabular array and look at some examples of Oracle updates. As with the INSERT section, I rolled back the changes to the original table.

To set up each author contract number to zero, simply leave off the WHERE clause. If you practise not specify a row, so all rows are updated when Oracle update is used.

SQL> select author_key, author_contract_nbr from writer;

AUTHOR_KEY AUTHOR_CONTRACT_NBR
----------- -------------------
A101 5601
A102 5602
A103 5603
A104 6602
A105 7896
A106 6547
A107 3452
A108 7954
A109 1
A110 2853

10 rows selected.

SQL> update writer set author_contract_nbr = 0000;

10 rows updated.

The command returns the table to the state it was in before the Oracle updates.

To modify the contract number for author A109 to 999, use the statement below. Discover that the WHERE clause identifies which row will be updated with Oracle UPDATE.

SQL> update
two author
iii set author_contract_nbr = 999
iv where
five author_key = 'A109';

ane row updated.

I can also set multiple columns in one Oracle update. A comma separates each column to be inverse. All of the columns identified will be inverse for all the rows specified in the WHERE clause.

SQL> update
two author
3 ready author_contract_nbr = 8888,
4 author_zip = 32076
5 where
half dozen author_state = 'MO';

3 rows updated.

Ane of the powerful features of the Oracle update statement is the power to update rows using a query.

update <table name> set (col1, col2, col3,?) = (<query>)
where <expression>;

The query must have a value in the select clause for each column in the column listing. If the where clause is not used all rows are updated when the Oracle update is executed.

SQL> update
2 sales
three set (order_date, quantity) = (select
4 SYSDATE,
five avg(quantity)
half-dozen from sales
vii where book_key = 'B102'
8 group past book_key, SYSDATE)
9 where book_key = 'B102';

11 rows updated.

The query in the Oracle UPDATE statement defines the values to update the columns. I still need the WHERE clause in the Oracle UPDATE argument to define which rows were to be updated.

So far, we can insert new rows, change rows already in the tabular array, and at present nosotros need a way to remove rows that we no longer want in the table.

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