---
name: "Data::Printer::Filter::DB"
section: "3pm"
platform: "linux"
package: "libdata-printer-perl"
version: "1.002001-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Data::Printer::Filter::DB"
---

# Data::Printer::Filter::DB(3pm)

pretty-printing database objects (DBI, DBIx::Class, etc)

## NAME

Data::Printer::Filter::DB - pretty-printing database objects (DBI, DBIx::Class, etc)

## SYNOPSIS

In your `".dataprinter"` file:

```
    filters = DB
```

You may also customize the look and feel with the following options (defaults shown):

```
    ### DBH settings:
    # expand database handle objects
    filter_db.connection_details = 1
    ### DBIx::Class settings:
    # signal when a result column is dirty:
    filter_db.show_updated_label = 1
    # signal when result rows contain extra columns:
    filter_db.show_extra_label = 1
    # override class.expand for schema dump
    filter_db.schema.expand = 1
    # expand DBH handle on schema dump (may touch DB)
    filter_db.schema.show_handle = 0
    # show source details (connected tables) on schema dump
    # (may be set to 'names', 'details' or 'none')
    filter_db.schema.loaded_sources = names
    # show source table name ResultSource objects
    filter_db.show_source_table = 1
    # show source columns ('names', 'details' or 'none'):
    filter_db.column_info = details
    # this plugin honors theme colors where applicable
    # and provides the following custom colors for you to use:
    colors.filter_db_connected    = #a0d332
    colors.filter_db_disconnected = #b3422d
```

That's it!

## DESCRIPTION

This is a filter plugin for Data::Printer that displays (hopefully) more relevant information on database objects than a regular dump.

### Parsed Modules

*DBI*

If it's a database handle, for example, this filter may show you something like this:

```
    SQLite Database Handle (connected) {
        dbname: file.db
        Auto Commit: 1
        Statement Handles: 2 (1 active)
        Last Statement: SELECT * FROM some_table
    }
```

You can show less information by setting this option on your `".dataprinter"`:

```
    filter_db.connection_details = 0
```

If you have a statement handler like this (for example):

```
    my $sth = $dbh->prepare('SELECT * FROM foo WHERE bar = ?');
    $sth->execute(42);
    use DDP; p $sth;
```

This is what you'll get:

```
    SELECT * FROM foo WHERE bar = ?  (42)
```

Note that if your driver does not support holding of parameter values, you'll get a `"bindings unavailable"` message instead of the bound values.

*DBIx::Class*

This filter is able to pretty-print many common DBIx::Class objects for inspection. Unless otherwrise noted, none of those calls will touch the database.

**DBIx::Class::Schema** objects are dumped by default like this:

```
    MyApp::Schema {
        connection: MySQL Database Handle (connected)
        replication lag: 4
        loaded sources: ResultName1, ResultName2, ResultName3
    }
```

If your `".dataprinter"` settings have `"class.expand"` set to `0`, it will only show this:

```
    MyApp::Schema (MySQL - connected)
```

You may override this with `"filter_db.schema.expand = 1"` (or 0). Other available options for the schema are (default values shown):

```
    # if set to 1, expands 'connection' into a complete DBH dump
    # NOTE: this may touch the database as it could try to reconnect
    # to fetch a healthy DBH:
    filter_db.schema.show_handle = 0
    # set to 'details' to view source details, or 'none' to skip it:
    filter_db.schema.loaded_sources = names
```

**DBIx::Class::ResultSource** objects will be expanded to show details of what that source represents on the database (as perceived by DBIx::Class), including column information and whether the table is virtual or not.

```
    User ResultSource {
        table: "user"
        columns:
            user_id integer not null auto_increment (primary),
            email varchar(100),
            bio text
        non-primary uniques:
            (email) as 'user_email'
    }
```

Ever got bit by DBIx::Class?

Let us know if we can help by creating an issue on Data::Printer's Github. Patches are welcome!

## SEE ALSO

Data::Printer