# List Of SQL Built-In Functions

SQL (Structured Query Language) has many built-in functions for performing calculations on different types of data.

We have categorized sql functions depends on their actions, which is:

• Aggregate | Group By Functions
• Char | String Functions
• Numeric | Math Functions
• Date & Time Functions

## SQL Aggregate Functions | Group By Functions

Function Name Description
SUM() The SUM() is a function, and return total sum of a table column from query result.
AVG() The AVG() is a function, and return average value of a table column from query result.
COUNT() The COUNT() is a function, and return total number of records or rows from query result.
MAX() The MAX() is a function, and return the largest or highest value of a numeric table column from query result.
MIN() The MIN() is a function, and return the lowest or minimum value of a numeric table column from query result.

## SQL Numeric Functions | Math Functions

Function Name Description
ABS() The ABS() is a function, and return absolute value of a given number from query result.
FLOOR() The FLOOR() is a function, and return previous whole integer (no fractional digits) value that is equal to or less than a given input floating number from query result.
CEILING() The CEILING() is a function, and return next whole integer(no fractional digits) value that is equal to or greater than a given input floating number from query result.
ROUND() The ROUND() function is used to round a numeric field (floating point value) to the whole number (integer value without fractional) of decimals specified.
RAND() The RAND() function is used to generate a floating-point number or whole integer number by randomly.
SQRT() The SQRT() is a function, and returns Double specifying the square root of a non-negative number.
POWER() The POWER() is a function, and returns the value of X raised to the power of Y.

## SQL Character Functions | String Functions

Function Name Description
LENGTH() The LEN() function returns the length of the value of a given input string or in a table field.
ASCII() The ASCII() is a function, and return a number (ascii value) that represent of a given character from query result.
CHAR() The CHAR() | CHR() is a function, and return a character (ascii value) that represent of a given input number from query result.
LCASE() | LOWER() The LCASE() | LOWER() is a function, and converts the value of a column to lowercase.
UCASE() | UPPER() The UCASE() | UPPER() is a function, and converts the value of a column to uppercase.
REPLACE() The REPLACE() function is used to replace one or more characters (sequence of characters or string) from a string or expression.
TRIM() The TRIM() function is used to removes all whitespaces (by default) or any specified character(by user defined) from a string.
CONCAT() The CONCAT() function is used to concatenate or joins strings from one or more string or expression.
REVERSE() The REVERSE() is a function, and returns a string in which the character order of a specified string is reversed.
CHARINDEX() | POSITION() The CHARINDEX() | LOCATE() | INSTR() is a function and returns the index position of the first occurrence of substring of a given input string or text.
LEFT() The LEFT() is a function, and extracts substring or number of characters from a given input string or text.
RIGHT() The RIGHT() is a function, and extracts substring or number of characters from a given input string or text.
MID() | SUBSTRING() The MID() | SUBSTRING() function is used to extract substring or number of characters from a given input string or data column.

## SQL Date Time Functions

Function Name Description
NOW() The NOW() is a function, and returns a date and time specifying the current date and time according your computer's system date and time.
DAY() The DAY() is a function, and return or extract the day value portion or day of the month (a whole integer number from 1 to 31) of a given input date value.
MONTH() The MONTH() is a function, and return or extract the month value (a whole integer number from 1 to 12) of a given input date value.
YEAR() The YEAR() is a function, and returns or extract year portion(a four digit number) of a given input date value.
HOUR() The HOUR() is a function, and return or extract the hour portion of a given input time value.
MINUTE() The MINUTE() is a function, and return or extract the minute portion of a given input time value.
SECOND() The SECOND() is a function, and return or extract the second portion of a given input time value.
DAYNAME() The DAYNAME() is a function, and returns the name of the weekday of a given input date value.
MONTHNAME() The MONTHNAME() is a function, and returns a string indicating the full name of the specified month of a given input date value.
DAYOFYEAR() The DAYOFYEAR() is a function, and returns a integer indicating day of the year of a given input date value.
DATEPART() | EXTRACT() The DATEPART() | EXTRACT() is a function, and returns a integer number containing the specified part of a given input date time value.