Category: SQL TUTORIAL
In this post, you will learn about the Oracle DUAL table which is a special table used for evaluating expressions or calling functions. Now let’s dig into more on …
In short, the difference between UNION operator and UNION ALL (UNION vs UNION ALL) operator is UNION gives unique results set in the output even though the combined result …
ALL_TAB_COLUMNS and ALL_TAB_COLS are the views in Oracle that describes the columns of the tables, views, and clusters accessible to the current user. The only difference between two views …
DENSE_RANK calculates the rank of a value in a group of values. The return type is NUMBER. If two or more rows tie for a rank, each tied rows …
METHOD-1: Below query will give a number of rows for the required tables but these are not accurate until we ANALYZE(gather stats) the tables. So we can not depend …
Lets take a look at differences between INTERVAL and ADD_MONTHS() in Teradata. This post mainly focused on where to use ADD_MONTHS() over INTERVAL function in Teradata. INTERVAL is a …
RANK Function: RANK function returns the rank of a value in a group of values. It is similar to DENSE_RANK function. The rank function can cause non-consecutive rankings if …
Indexes are special lookup tables that the database search engine can use to speed up data retrieval. To simply put, an index is a pointer to data in a …
