When you want to search for the value of a particular element rather than the entire array, the Pl/sql associative array is useful for arrays of name-value pairs of types. Applying 11g Documents "It's like a simple version of a SQL table, you can
1) classification of Sets
Oracle supports three types of collections:
Associative array (Index-by table)
Nested table)
Variable-length array (VARRAY)
One of their differences is that the Nested table and VARRY can be used either in PL/SQL or
Combined arrays are previously called PLSQL tables. Union arrays cannot be used in tables. They can only be used as structures for programming. Union Arrays can only be accessed in PLSQL
A union array is previously called a PL/SQL table. Union
These days to see the Oracle PL/SQL Real-combat this book, out of the study of the performance of the statement, the downstream standard on the impact of the code.1. Progressive processingThe program declares a cursor c1, and then implicitly opens
The significance of understanding Oracle collections is that when we develop applications using programming languages, we use a lot of built-in Collection types, such as arrays and linked lists.
The significance of understanding Oracle collections
The federated Array was formerly called the Pl/sql table. Federated arrays cannot be used in tables and can only be used as a structural body for programming. Federated arrays can only be accessed in Pl/sql.
It is important to note that some of the
Document directory
Restrictions on nocopy
With the nocopy prompt, you can change the in/In out type parameters of the process from by value to by referencetuning PL/SQL procedure callwith the nocopy compiler hint
By default,OUTAndIN OUTParameters
We know that it is expensive to run SQL statements in a PL/SQL program, because they are being submitted to the SQL engine for processing, and this control transfer between the PL/SQL engine and the SQL engine is called the context, and each time it
Content
Define Collection type
Declare Collection variables
Initialize and reference Collection
Reference Collection Element
Assign a value to Collection
Multi-dimensional Collection
Compare Collection
Collection Method
Collection
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