Sql updating a table from the same table Free chat punjabi
He is also one of the leading posters at a moderator at , which allow you to declare nested tables, associative arrays, and variable-size arrays.They let you reference individual elements for array operations, or manipulate the collection as a whole.
You can think of a record as a variable that can hold a table row, or some columns from a table row. The following sections discuss PL/SQL collections and records: Although collections have only one dimension, you can model multi-dimensional arrays by creating collections whose elements are also collections.
To use collections in an application, you define one or more PL/SQL types, then define variables of those types.
That gives you array-like access to individual rows.
Nested tables differ from arrays in two important ways: are called varrays.
The usual way to write the update method is as shown below: The issue with this query is that it will take a lot of time as it affects 2 million rows and also locks the table during the update.