1.5.1. Usage

1.5.1.1. Instantiation

Create an information-discovery object with a corresponding connection:

use Atlas\Info\Info;
use Atlas\Pdo\Connection;

$connection = Connection::new('sqlite::memory:');
$info = Info::new($connection);

Note:

The new() method will automatically pick the right schema-discovery class for your Connection.

1.5.1.2. Fetching Table Names

To get an array of table names from the current schema, call fetchTableNames().

$tableNames = $info->fetchTableNames();
foreach ($tableNames as $tableName) {
    echo $tableName . PHP_EOL;
}

You can also indicate that you want table names from another schema:

$tableNames = $info->fetchTableNames('schema_name');

1.5.1.3. Fetching Column Defintions

To get an array of column definitions in a table, call fetchColumns().

$columns = $info->fetchColumns('table_name');
foreach ($columns as $name => $def) {
    echo "Column $name is of type "
       . $def['type']
       . " with a size of "
       . $def['size']
       . PHP_EOL;
}

Tip:

You can use a schema prefix on the table name if you like, such as 'schema_name.table_name'.

Each element is itself an array, with the following keys:

  • name: (string) The column name

  • type: (string) The column data type. Data types are as reported by the database.

  • size: (?int) The column size (character length for strings, or numeric precision for numbers).

  • scale: (?int) The number of decimal places for the column, if any.

  • notnull: (bool) Is the column marked as NOT NULL?

  • default: (mixed) The default value for the column. Note that this will be null if the underlying database uses an SQL expression instead of a literal string or number.

  • autoinc: (bool) Is the column auto-incremented?

  • primary: (bool) Is the column part of the primary key?

1.5.1.4. Fetching Auto-Increment Sequence Name

To fetch the name of the primary key autoincrement sequence on a PostgreSQL table, call fetchAutoincSequence() with the table name.

$sequence = $info->fetchAutoincSequence('table_name');
// => 'table_name_id_seq'

On systems other than PostgreSQL, this will return null.