What is collections in PL SQL?

What is collections in PL SQL?

A collection is an ordered group of elements having the same data type. Each element is identified by a unique subscript that represents its position in the collection.

What are the collections in Oracle?

Collections in Oracle PL/SQL

• Index-By Tables (Associative Arrays)
• Nested Table Collections.
• Varrays Collections.
• Assignments and Equality Tests.
• Collection Methods.
• MULTISET Operators. MULTISET UNION {ALL | DISTINCT} Operator.
• MULTISET Conditions. IS {NOT} A SET Condition.
• MULTISET Functions. CARDINALITY Function.

What are the PL SQL built in collection methods?

You can use the methods EXISTS , COUNT , LIMIT , FIRST , LAST , PRIOR , NEXT , EXTEND , TRIM , and DELETE to manage collections whose size is unknown or varies. EXISTS , COUNT , LIMIT , FIRST , LAST , PRIOR , and NEXT are functions that check the properties of a collection or individual collection elements.

Can we create multi dimensional collection in PL SQL?

Description PL/SQL doesn’t offer native support for multi-dimensional arrays, as you will find in other programming languages. You can, however, emulate these structures using nested collections.

What are different types of collections?

Some important collection classes are ArrayList, LinkedList, HashMap, TreeMap, HashSet, and TreeSet. These classes solve most of our programming needs but if we need some special collection class, we can extend them to create our custom collection class.

What is collection method?

Data collection is a process of collecting information from all the relevant sources to find answers to the research problem, test the hypothesis and evaluate the outcomes. Data collection methods can be divided into two categories: secondary methods of data collection and primary methods of data collection.

What are collection attributes?

An attribute collection is a group of item or category attributes that is associated or behave the same way in a context. Attribute collections are used for workflow step validation and catalog and hierarchy views.

What is bulk collect in PL SQL?

A bulk collect is a method of fetching data where the PL/SQL engine tells the SQL engine to collect many rows at once and place them in a collection. The SQL engine retrieves all the rows and loads them into the collection and switches back to the PL/SQL engine. The data can now be processed as needed in memory.

How do you initialize a collection in PL SQL?

To create collections, you define a collection type, then declare variables of that type. You can define TABLE and VARRAY types in the declarative part of any PL/SQL block, subprogram, or package. Collections follow the same scoping and instantiation rules as other types and variables.