NAME

Raku TOP Storage - The parent roles Raku TOP Storage classes

TITLE

Raku TOP Storage

SUBTITLE

The parent roles Raku TOP Storage classes

AUTHOR

Tim Nelson - https://github.com/wayland

Database::Storage

The parent class for all the different Database Storage classes (aka drivers, backends).

role	Database::Storage

Methods

.useTable

method	useTable(Table :$table, *%params)

Returns a table belonging to the database. Parameters vary depending on the Storage type.

Table::Storage

role	Table::Storage does Associative does Positional {

Attributes

Field @.fields

Stores the fields

%.field-indices

For looking up fields by name

Methods

.new

Creates a Table::Storage.

.new(Database::Storage :$database, Relation :$frontend-object, Str :$action, Str :%fields)

Parameters to .new are:

Relation $frontend-object

The frontend object that is using this storage object.

Database::Storage :$database

The Database::Storage with which this Table::Storage is connected.

Str $action

The action to take -- see the parameter of the same name on the frontend object

Str %fields

If relevant, the fields to use in creating/altering the table

Str $field-mode = 'Automatic'

$!field-mode could be one of the following:

• Automatic: extra fields create new columns (default); like a spreadsheet

• Error: extra fields create an error; like a RDBMS

• overflow: extra fields get stuck in a (JSON?) hash/object/assoc field; the name of the field is in $!overflow-field-name

Str $overflow-field-name

The name of the field the overflow fields get put in

exists

Returns True if the table already exists.

method	.exists(Str :$true-error, Str :$false-error)

If false-error is passed, and the table doesn't exist, the function will die with the passed error.

format

Outputs the current table using the specified formatter. This is for outputting tables in ASCII, Unicode Box, CSV, and maybe someday HTML.

Parameters are:

Str $format = 'HalfHuman';

Specifies what the output format is

%parameters

Parameters passed to TOP::Formatter::*.new()

parse

Reads data into a table from the specified format. As with the above, this is for reading tables in ASCII, Unicode Box, CSV, and the like.

Parameters are:

Str $format = 'HalfHuman';

Specifies what the input format is

%parameters

Parameters passed to TOP::Parser::*.new()

.add-field

Adds a field to the table

.add-field(Table :$relation, Str :$name, Any:U :$type)

Str $name

The name of the field being added

Any:U $type

The type of the field, as a Raku type