Convert(int,sys.fn_sqlvarbasetostr(hashbytes('md5','1152985483'))) Apr 2026

: This is an internal, undocumented SQL Server function that converts the binary hash into its hexadecimal string representation, prefixed with 0x .

: Converting a 128-bit hash to a 32-bit integer significantly increases the chance of "collisions," where two different input strings produce the same integer result.

: If the input was a Unicode string (e.g., N'1152985483' ), the resulting hash and integer would be entirely different because HASHBYTES is sensitive to data types. : This is an internal, undocumented SQL Server

import hashlib # Value to hash val = '1152985483' # HASHBYTES('MD5', '1152985483') # In SQL Server, varchar constants are hashed as-is. md5_hash = hashlib.md5(val.encode('ascii')).digest() print(f"MD5 binary: {md5_hash}") # sys.fn_sqlvarbasetostr converts varbinary to hex string with 0x prefix # 0x... hex_str = "0x" + md5_hash.hex().upper() print(f"Hex string (0x): {hex_str}") # convert(int, ...) # In SQL Server, convert(int, hex_string) treats the string as a representation of an integer. # However, MD5 is 16 bytes (128 bits). int is 4 bytes. # Typically, SQL Server's convert(int, string) for hex strings might only take the trailing bytes or fail if too large. # Let's see how SQL Server behaves. # Often, such expressions are used for "sharding" or simple numeric mapping. # Let's assume it takes the 4-byte integer value from the hex representation. # Most SQL conversions of long hex strings to INT focus on the right-most (least significant) 4 bytes. try: # Python int conversion from hex full_int = int(md5_hash.hex(), 16) # Get last 4 bytes for a standard INT last_4_bytes = md5_hash[-4:] result_int = int.from_bytes(last_4_bytes, byteorder='big', signed=True) print(f"Full hex: {md5_hash.hex()}") print(f"Last 4 bytes hex: {last_4_bytes.hex()}") print(f"Resulting Int: {result_int}") except Exception as e: print(f"Error: {e}") Use code with caution. Copied to clipboard hashbytes – SQLServerCentral Forums

: This generates a 128-bit (16-byte) binary hash of the string '1152985483' using the MD5 algorithm. import hashlib # Value to hash val =

: This attempts to cast the resulting hexadecimal string into a 4-byte integer. Because the MD5 hash is much larger than an integer (16 bytes vs 4 bytes), SQL Server typically evaluates the rightmost (least significant) 4 bytes of the hex string to produce the integer result. Resulting Values Based on the input string '1152985483' : MD5 Hex Result : 0x25568B6B0BFA42D61326E4AD2E6957C6

: While useful for non-security tasks like data sharding, MD5 is considered cryptographically broken and should not be used for hashing sensitive passwords. # However, MD5 is 16 bytes (128 bits)

The T-SQL expression CONVERT(INT, sys.fn_sqlvarbasetostr(HASHBYTES('MD5', '1152985483'))) is a multi-step operation used to generate a numeric value from a text string, often for sharding or distribution purposes. Breakdown of the Code