Author: Dev

A B-tree index in Oracle’s PL/SQL is a data structure that allows for efficient retrieval of data in a database table. The term “B-tree” stands for balanced tree, and it’s a type of self-balancing search tree data structure. B-tree indexes are commonly used in database management systems to speed up the retrieval of data by…(Continue Reading)

An index is a database structure that can be used to improve the performance of SQL queries. An PL/SQL index is a schema object that has the role to provide direct and fast access without reading the entire table. Indexes can be created on one or more columns in a table, and they can be…(Continue Reading)

PL/SQL Data Types Oracle PL/SQL has a variety of data types that can be used to declare variables, constants, and record fields. Oracle PL/SQL includes a variety of data types that can be used to store and manipulate different types of data within the database. The most commonly used data types in Oracle PL/SQL include:…(Continue Reading)

ORA-30484: missing window specification for this function Oracle PL/SQL error message: ORA-30484: missing window specification for this function. Cause: All window functions should be followed by window specification, like () OVER () Solution: Correct the syntax, then retry the operation. Example: select name, price, rank() (order by price desc) course_rank from course ; Output: ORA-30484:…(Continue Reading)

ORA-30483: window functions are not allowed here Oracle PL/SQL error message: ORA-30483: window functions are not allowed here. Cause: Window functions are allowed only in the SELECT list of a query. A window function cannot be a group function. Solution: Correct the syntax, then retry the operation. Course table COURSE_ID NAME PRICE 1 SQL 1…(Continue Reading)