SQL Function Reference: Oracle vs. SQL Server

Math Functions
Function	Oracle	SQL Server
Absolute value	ABS	ABS
Arc cosine	ACOS	ACOS
Arc sine	ASIN	ASIN
Arc tangent of n	ATAN	ATAN
Arc tangent of n and m	ATAN2	ATN2
Smallest integer >= value	CEIL	CEILING
Cosine	COS	COS
Hyperbolic cosine	COSH	COT
Exponential value	EXP	EXP
Round down to nearest integer	FLOOR	FLOOR
Natural logarithm	LN	LOG
Logarithm, any base	LOG(N)	N/A
Logarithm, base 10	LOG(10)	LOG10
Modulus (remainder)	MOD	USE MODULO (%) OPERATOR
Power	POWER	POWER
Random number	N/A	RAND
Round	ROUND	ROUND
Sign of number	SIGN	SIGN
Sine	SIN	SIN
Hyperbolic sine	SINH	N/A
Square root	SQRT	SQRT
Tangent	TAN	TAN
Hyperbolic tangent	TANH	N/A
Truncate	TRUNC	N/A
Highest number in list	GREATEST	N/A
Lowest number in list	LEAST	N/A
Convert number if NULL	NVL	ISNULL
Standard deviation	STDDEV	STDEV
Variance	VARIANCE	VAR

String Functions
Function	Oracle	SQL Server
Convert character to ASCII	ASCII	ASCII
String concatenate	CONCAT	(expression + expression)
Convert ASCII to character	CHR	CHAR
Return starting point of character in character string (from left)	INSTR	CHARINDEX
Convert characters to lowercase	LOWER	LOWER
Convert characters to uppercase	UPPER	UPPER
Pad left side of character string	LPAD	N/A
Remove leading blank spaces	LTRIM	LTRIM
Remove trailing blank spaces	RTRIM	RTRIM
Starting point of pattern in character string	INSTR	PATINDEX
Repeat character string multiple times	RPAD	REPLICATE
Phonetic representation of character string	SOUNDEX	SOUNDEX
String of repeated spaces	RPAD	SPACE
Character data converted from numeric data	TO_CHAR	STR
Substring	SUBSTR	SUBSTRING
Replace characters	REPLACE	STUFF
Capitalize first letter of each word in string	INITCAP	N/A
Translate character string	TRANSLATE	N/A
Length of character string	LENGTH	DATALENGTH or LEN
Greatest character string in list	GREATEST	N/A
Least character string in list	LEAST	N/A
Convert string if NULL	NVL	ISNULL

Date Functions
Function	Oracle	SQL Server
Date addition	(use +)	DATEADD
Date subtraction	(use -)	DATEDIFF
Last day of month	LAST_DAY	N/A
Time zone conversion	NEW_TIME	N/A
First weekday after date	NEXT_DAY	N/A
Convert date to string	TO_CHAR	DATENAME
Convert date to number	TO_NUMBER(TO_CHAR())	DATEPART
Convert string to date	TO_DATE	CAST
Get current date and time	SYSDATE	GETDATE()

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