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How to add a column of another data from another column?
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Alzabo::Runtime::Column(3pm) User Contributed Perl Documentation Alzabo::Runtime::Column(3pm) NAME
Alzabo::Runtime::Column - Column objects SYNOPSIS
use Alzabo::Runtime::Column; DESCRIPTION
This object represents a column. It holds data specific to a column. INHERITS FROM
"Alzabo::Column" Note: all relevant documentation from the superclass has been merged into this document. METHODS
table Returns the table object to which this column belongs. name Returns the column's name as a string. nullable Returns a boolean value indicating whether or not NULLs are allowed in this column. attributes A column's attributes are strings describing the column (for example, valid attributes in MySQL are 'UNSIGNED' or 'ZEROFILL'. This method returns a list of strings of such strings. has_attribute This method can be used to test whether or not a column has a particular attribute. By default, the check is case-insensitive. It takes the following parameters: * attribute => $attribute * case_sensitive => 0 or 1 (defaults to 0) It returns a boolean value indicating whether or not the column has this particular attribute. type Returns the column's type as a string. sequenced The meaning of a sequenced column varies from one RDBMS to another. In those with sequences, it means that a sequence is created and that values for this column will be drawn from it for inserts into this table. In databases without sequences, the nearest analog for a sequence is used (in MySQL the column is given the AUTO_INCREMENT attribute, in Sybase the identity attribute). In general, this only has meaning for the primary key column of a table with a single column primary key. Setting the column as sequenced means its value never has to be provided to when calling "Alzabo::Runtime::Table->insert". Returns a boolean value indicating whether or not this column is sequenced. default Returns the default value of the column as a string, or undef if there is no default. default_is_raw Returns true if the default is intended to be provided to the DBMS as-is, without quoting, fore example "NOW()" or "current_timestamp". length Returns the length attribute of the column, or undef if there is none. precision Returns the precision attribute of the column, or undef if there is none. is_primary_key Returns a boolean value indicating whether or not this column is part of its table's primary key. is_numeric Returns a boolean value indicating whether the column is a numeric type column. is_integer Returns a boolean value indicating whether the column is a numeric type column. is_floating_point Returns a boolean value indicating whether the column is a numeric type column. is_character Returns a boolean value indicating whether the column is a character type column. This is true only for any columns which are defined to hold text data, regardless of size. is_date Returns a boolean value indicating whether the column is a date type column. is_datetime Returns a boolean value indicating whether the column is a datetime type column. is_time Returns a boolean value indicating whether the column is a time type column. is_time_interval Returns a boolean value indicating whether the column is a time interval type column. is_blob Returns a boolean value indicating whether the column is a blob column. This is true for any columns defined to hold binary data, regardless of size. generic_type This methods returns one of the following strings: integer floating_point character date datetime time blob unknown definition The definition object is very rarely of interest. Use the "type()" method if you are only interested in the column's type. This methods returns the "Alzabo::Runtime::ColumnDefinition" object which holds this column's type information. comment Returns the comment associated with the column object, if any. alias Takes the following parameters: * as => $name This method returns an object that can be used in calls to the table and schema "select()" methods in order to change the name given to the column if "next_as_hash()" is called on the "Alzabo::DriverStatement" returned by the aforementioned "select()" method. AUTHOR
Dave Rolsky, <autarch@urth.org> perl v5.8.8 2007-12-23 Alzabo::Runtime::Column(3pm)
