What is index by table in PL SQL?

An index-by table (also called an associative array) is a set of key-value pairs. Each key is unique and is used to locate the corresponding value. The key can be either an integer or a string.

What is the difference between index by table and index by table record?

TABLE OF defines the type of a collection’s field(s), which can be a datatype (i.e. TABLE OF NUMBER ) or a record type (i.e. TABLE OF MY_TABLE%TYPE ). INDEX BY refers to the method of looking up this collection, almost like a key-value pair.

Which of the following is true about PL SQL index by tables?

Which of the following is true about PL/SQL index-by tables? It is a set of key-value pairs. Each key is unique and is used to locate the corresponding value.

What is Varray in PL SQL?

A VARRAY is a type of collection in which each element is referenced by a positive integer called the array index. The maximum cardinality of the VARRAY is specified in the type definition. The TYPE IS VARRAY statement is used to define a VARRAY collection type.

What is the difference between Varray and nested table in Oracle?

Differences Between Varrays And Nested Tables A Varray which is stored in a database maintains its subscripts and sequence. It is always maintained as a single object. Whereas, the nested tables are used when the count of the number of elements is not restricted.

What is a table index?

Table indexes work the same way as an index in a book does, allowing you to quickly find information contained in the table. Table indexes are commonly made by using one column in a table, but can also contain more than one column. Indexed columns are the columns that are used within your queries to find information.

What is a table index in Oracle?

An index is a schema object that contains an entry for each value that appears in the indexed column(s) of the table or cluster and provides direct, fast access to rows. Oracle Database supports several types of index: Normal indexes.

Can we delete record from Varray in Oracle?

However, you cannot update or delete individual varray elements directly with SQL; you have to select the varray from the table, change it in PL/SQL, then update the table to include the new varray. You can also do this with nested tables, but nested tables have the option of doing piecewise updates and deletes.