General Functions:
NVL, NVL2
Character Functions:
NVL, NVL2
Character Functions:
Character functions accept character data as an input and can return both character and numeric values. Character functions can be divided into case-conversion and character manipulation types.
LOWER, UPPER, INITCAP are the three case conversion functions.
Some Character -manipulations functions are : CONCAT, SUBSTR, INSTR, LENGTH, LPAD, TRIM
Number functions:
Number functions accept numeric input and return numeric input.
ROUND: rounds to the nearest unit of 100.
TRUNC: truncates the column, or value to n decimal places.
MOD: finds the reminder of the first argument divided by second argument. It is frequently used to determine whether a value is odd or even.
Date related functions:
Oracle's default date format is : DD-MON-RR. RR date is similar to YY but it also specify century. RR determines the default value for century in INSERT.
SYSDATE function:
Returns current database server date and time. If your database in London and you are in California, it will display London current time. If you want California time use - CURRENT_DATE function. You can use arithmetic operators with SYSDATE function.
Date-Manipulation functions : MONTHS_BETWEEN, ADD_MONTHS, NEXT_DAY, ROUND, TRUNC, and LAST_DAY
Date function can be combined with Arithmetic function: date+number, Date-number, date-date, Date +number/24.
Data Type Conversion:
TO_NUMBER, TO_DATE, TO_CHAR, TO_DATE
Nesting Functions:
Nested functions are evaluated from deepest to the least deep level.
Group functions :
Number functions accept numeric input and return numeric input.
ROUND: rounds to the nearest unit of 100.
TRUNC: truncates the column, or value to n decimal places.
MOD: finds the reminder of the first argument divided by second argument. It is frequently used to determine whether a value is odd or even.
Date related functions:
Oracle's default date format is : DD-MON-RR. RR date is similar to YY but it also specify century. RR determines the default value for century in INSERT.
SYSDATE function:
Returns current database server date and time. If your database in London and you are in California, it will display London current time. If you want California time use - CURRENT_DATE function. You can use arithmetic operators with SYSDATE function.
Date-Manipulation functions : MONTHS_BETWEEN, ADD_MONTHS, NEXT_DAY, ROUND, TRUNC, and LAST_DAY
Date function can be combined with Arithmetic function: date+number, Date-number, date-date, Date +number/24.
Data Type Conversion:
TO_NUMBER, TO_DATE, TO_CHAR, TO_DATE
Nesting Functions:
Nested functions are evaluated from deepest to the least deep level.
Group functions :
Group functions operates in multiple rows and gives a one result per group. Group functions ignores null values. AVG, SUM, MIN, MAX, COUNT
