Alzabo::QuickRef(3pm)

🦋 NAME 🦋

Alzabo::QuickRef — a quick reference to methods in the Alzabo classes. yes bestie, it's literally the cheat sheet 💅✨

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🌸 GENERAL 🌸

Okay so this reference is your lil pocket guide to some of the more commonly used methods that Alzabo hands you. And bonus: it also gives you an idea of which classes contain which types of methods, so when you're sitting there like "how do I even do this thing??" you actually know where to go look. 🫶

💖 Alzabo, Alzabo::Create, and Alzabo::Runtime

These modules? Mostly they just get used to load other modules. That's it, that's the whole job. 🙈

But Alzabo::Runtime has a lil glow-up: it can preload schemas at compile time by doing:

use Alzabo::Runtime qw( schema1 schema2 schema3 );

💖 Alzabo::MethodMaker

This module can be used to generate a whole bunch of useful convenience methods. How? By auto-generating methods in new packages and re-blessing some of the schema objects into those packages. lowkey iconic.

To have it generate all the possible methods for a schema, you'd do:

use Alzabo::MethodMaker ( schema => 'some_schema',
                          # Root for new packages
                          class_root => 'My::Data',
                          # Make all possible methods
                          all => 1 );

This will make convenience methods for things like getting table and column objects, following various types of foreign keys, and getting data from row objects. slay 💅

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🔥 METHODS 🔥

🍓 Retrieving data

Alzabo::Runtime::Schema

This object lets you connect to the database. It contains several data retrieval methods, including join.

• load_from_file — load an existing schema object from disk. Returns a new schema object. 🎀
• set_user ($user) — set the username to be used when connecting to the database.
• set_password ($password) — set the password to be used when connecting to the database.
• set_host ($host) — set the host to be used when connecting to the database.
• connect (%params) — connect to the RDBMS. This will use the previously set username/password/host, though those can be overridden by the %params given to the call.

⚠️ Important: this method must be called before any data retrieval is attempted. no skipping, bestie, I mean it.

• join — fetch rows from one or more tables based on a table join. Returns either an Alzabo::Runtime::RowCursor or Alzabo::Runtime::JoinCursor object.
• function/select — lets you execute arbitrary column aggregate SQL functions such as AVG or MAX with a multi-table join.
• table ($name) — returns an Alzabo::Runtime::Table object. This one matters a lot, because most of the row fetching operations are table object methods. iykyk.

Alzabo::Runtime::Table

Objects in this class have methods that let you insert new rows and retrieve existing data in the form of Alzabo::Runtime::Row or Alzabo::Runtime::RowCursor objects.

• All methods that return a single row return an Alzabo::Runtime::Row object.
• All methods that return multiple rows return an Alzabo::Runtime::RowCursor object.
• All methods that return rows can be given the no_cache parameter, which ensures that the row(s) returned will not be cached. Rows obtained this way should not be updated or deleted, because that will play havoc with the caching system. See the Alzabo::Runtime::Row documentation for more details.
• All methods that return multiple rows in the form of a cursor object can take an order_by parameter. See the Alzabo::Runtime::Table documentation for more details.
• insert — insert a new row and return it. ✨
• row_by_pk — returns the row identified by the primary key given.
• rows_where — retrieves a set of rows based on a where clause. Please see the method documentation for details on how where clauses are constructed.
• all_rows — retrieves all the rows in the table. every single one. 🫶
• function/select — lets you execute arbitrary column aggregate SQL functions such as AVG or MAX.
• potential_row — make a new Alzabo::Runtime::Row in the potential state.

Alzabo::Runtime::Row

Objects in this class represent a single row of data. You can retrieve the actual column values from it, update it, or delete it. main character energy, fr.

• select (@list_of_column_names) — given a list of column names, this method returns the values for those columns.
• update (%hash_of_columns_and_values) — given a hash of columns and values, this method will update the database and the object to match those values.
• delete — deletes the row from the database. Further attempts to retrieve data from this row will throw an exception. 💀 brutal but true.
• rows_by_foreign_key — given a foreign key object from the row's table to another table, returns either an Alzabo::Runtime::Row object or an Alzabo::Runtime::RowCursor object for the row(s) in the table to which the relationship exists, based on the value of the relevant column(s) in the current row.

This method can also take a no_cache and/or order_by parameter.

Alzabo::Runtime::RowCursor

Objects in this class are used to return multiple rows as a cursor, rather than as a list. This is much more efficient — at the expense of a few extra lines in your code. trade-offs, bestie, we love efficiency 💅

• next — returns the next Alzabo::Runtime::Row object, or undef if there are no more.
• all_rows — returns a list of all the remaining Alzabo::Runtime::Row objects, or an empty list if there are no more.

🧚 Creating/removing a schema

Alzabo::Create::Schema

This object represents a schema, and it contains one or more table objects. It's only used when creating or altering a schema, as opposed to when fetching data. Data manipulation happens via the Alzabo::Runtime::* classes.

• reverse_engineer — connect to a database and reverse engineer a schema. Returns a new schema object. 🦋
• load_from_file — load an existing schema object from disk. Returns a new schema object.
• create — if the schema has not yet been instantiated in an RDBMS, this method will instantiate the schema. If it has been previously instantiated, it will bring the schema in the RDBMS into sync with its object representation (altering tables/columns, etc.). Where possible, existing data will be preserved. 🫶
• make_sql — returns an array, each element of which is a SQL statement. The SQL is either the SQL to create the schema from scratch or the SQL needed to update the RDBMS to match the current object. See the create method for more details.
• drop — drop the database from the RDBMS where it was created. Does not remove the schema object itself from disk. careful, bestie 😭
• delete — delete the schema object files from disk. Does not drop the database from the RDBMS.

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👑 AUTHOR 👑

Dave Rolsky, <autarch@urth.org>

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and that's the whole page, babe 💖 this absolute gem is from perl v5.34.0, dated 2022-06-14 — go forth and query, you're gonna ate it 🌈🌸✨