Convert(int,sys.fn_sqlvarbasetostr(hashbytes('md5','1455985476')))

: Creating a non-obvious integer ID from a sensitive string.

: This attempts to cast that hex string into a 4-byte integer. Because the hash is much larger than an integer, SQL Server typically truncates the value, often resulting in an arithmetic overflow or returning a signed integer based on the last 4 bytes of the hash. The Result : Creating a non-obvious integer ID from a sensitive string

: This generates a 128-bit MD5 hash of the input string, returned as a varbinary value. SQL Server typically truncates the value

: Selecting a deterministic but seemingly random subset of rows (e.g., WHERE ABS(HashConvert) % 10 = 0 for a 10% sample). : Creating a non-obvious integer ID from a sensitive string

: This internal (undocumented) function converts the binary hash into its string representation (e.g., '0x792106533f84b730c64951a1ea702c78' ).