![]() ![]() Vertica NULL values translate to Perl's undefined ( undef) value. You can use several different date and time handling Perl modules to manipulate these values in your scripts. All interval data types (DATE, TIMESTAMP, etc.) are converted to strings. ![]() For this reason, Perl has little problem extracting most string and numeric data types from Vertica. It converts between string and numeric values based on the operations being performed on the values. Perl is a loosely-typed programming language that does not assign specific data types to values. A program that asks for and compares a password.Conversions Between Perl and Vertica Data Types With a password stored in a special file. Listing 14.2 is an example ofĪ program that prompts the user for a password and compares it You can use crypt to set up a password checker similar Of result are the two characters specified in salt. String is encrypted using the resulting key. Two characters can be any letter or digit, or one of the. The DES algorithm (to make it more difficult to decode). Is a character string of two characters that defines how to change Original is the string to be encrypted, and salt The crypt function encrypts a string using the NBS Data The end-of-line specifier.) The total number of characters removed,Ĥ (two from the first element and two from the last), is returnedįor more information on the $/ system variable, refer to Day 17, "System Variables. (The second element is ignored, because it is not terminated by The call to chomp in line 8 checks each element of first element is converted from test1:: to test1,Īnd the last element is converted from test3:: to test3. The number of characters removed, 2, is returned by chomp The call to chomp in line 5 converts the value ![]() ![]() The input line separator from both a scalar variable and an array Is the total number of characters removed by chomp. Of the list is checked for the input end-of-line string. IfĪs in the chop function, var can be either a Line separator defined by the $/ system variable. The last characters of a string or list of strings match the input The chomp function, defined only in Perl 5, checks whether $lastchar = assigns f, the last character of the last element Last element of the list is = ("ab", "cd", "ef") If chop is passed a list, the last character from the This call to chop assigns 5 to the scalar variable For example, to read an entire input file into anĪrray variable and remove all of the trailing newline characters,Ĭhop returns the character chopped. In thisĬase, chop removes the last character from every element The argument passed to chop can also be a list. # $mystring now contains "This is a strin" Ĭhop is used most frequently to remove the trailing newlineĬharacter from an input line, as follows: Var can be either a scalar value or a list, as described Scalar Values." It removes the last character from a scalar The chop function was first discussed on Day 3, "Understanding On which functions are supported or emulated on your machine Running UNIX, some of these functions might not be defined or mightĬheck the documentation supplied with your version of Perl for details If you are using Perl on a machine that is not Many of the functions described in today's lesson use features of the
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |