NAME¶
Alzabo::Runtime::Index - Index objects
SYNOPSIS¶
use Alzabo::Runtime::Index;
DESCRIPTION¶
This object represents an index on a table. Indexes consist of columns and
optional prefixes for each column. The prefix specifies how many characters of
the columns should be indexes (the first X chars). Some RDBMS's do not have a
concept of index prefixes. Not all column types are likely to allow prefixes
though this depends on the RDBMS. The order of the columns is significant.
INHERITS FROM¶
"Alzabo::Index"
Note: all relevant documentation from the superclass has been merged into this
document.
METHODS¶
columns¶
Returns an ordered list of the "Alzabo::Runtime::Column" objects that
are being indexed.
prefix ("Alzabo::Runtime::Column" object)¶
A column prefix is, to the best of my knowledge, a MySQL specific concept, and
as such cannot be set when using an RDBMSRules module for a different RDBMS.
However, it is important enough for MySQL to have the functionality be
present. It allows you to specify that the index should only look at a certain
portion of a field (the first N characters). This prefix is required to index
any sort of BLOB column in MySQL.
This method returns the prefix for the column in the index. If there is no
prefix for this column in the index, then it returns undef.
unique¶
Returns a boolean value indicating whether the index is a unique index.
fulltext¶
Returns a boolean value indicating whether the index is a fulltext index.
function¶
For function indexes, this returns the function being indexed.
The id is generated from the table, column and prefix information for the index.
This is useful as a canonical name for a hash key, for example.
Returns a string that is the id which uniquely identifies the index in this
schema.
table¶
Returns the "Alzabo::Runtime::Table" object to which the index
belongs.
AUTHOR¶
Dave Rolsky, <autarch@urth.org>