function Schema::introspectSchema

Same name in other branches
  1. 8.9.x core/lib/Drupal/Core/Database/Driver/sqlite/Schema.php \Drupal\Core\Database\Driver\sqlite\Schema::introspectSchema()
  2. 10 core/modules/sqlite/src/Driver/Database/sqlite/Schema.php \Drupal\sqlite\Driver\Database\sqlite\Schema::introspectSchema()
  3. 11.x core/modules/sqlite/src/Driver/Database/sqlite/Schema.php \Drupal\sqlite\Driver\Database\sqlite\Schema::introspectSchema()

Find out the schema of a table.

This function uses introspection methods provided by the database to create a schema array. This is useful, for example, during update when the old schema is not available.

Parameters

$table: Name of the table.

Return value

array An array representing the schema.

Throws

\Exception If a column of the table could not be parsed.

9 calls to Schema::introspectSchema()
Schema::addField in core/modules/sqlite/src/Driver/Database/sqlite/Schema.php
Add a new field to a table.
Schema::addPrimaryKey in core/modules/sqlite/src/Driver/Database/sqlite/Schema.php
Add a primary key.
Schema::changeField in core/modules/sqlite/src/Driver/Database/sqlite/Schema.php
Change a field definition.
Schema::dropField in core/modules/sqlite/src/Driver/Database/sqlite/Schema.php
Drop a field.
Schema::dropPrimaryKey in core/modules/sqlite/src/Driver/Database/sqlite/Schema.php
Drop the primary key.

... See full list

File

core/modules/sqlite/src/Driver/Database/sqlite/Schema.php, line 484

Class

Schema
SQLite implementation of \Drupal\Core\Database\Schema.

Namespace

Drupal\sqlite\Driver\Database\sqlite

Code

protected function introspectSchema($table) {
    $mapped_fields = array_flip($this->getFieldTypeMap());
    $schema = [
        'fields' => [],
        'primary key' => [],
        'unique keys' => [],
        'indexes' => [],
    ];
    $info = $this->getPrefixInfo($table);
    $result = $this->connection
        ->query('PRAGMA ' . $info['schema'] . '.table_info(' . $info['table'] . ')');
    foreach ($result as $row) {
        if (preg_match('/^([^(]+)\\((.*)\\)$/', $row->type, $matches)) {
            $type = $matches[1];
            $length = $matches[2];
        }
        else {
            $type = $row->type;
            $length = NULL;
        }
        if (isset($mapped_fields[$type])) {
            [
                $type,
                $size,
            ] = explode(':', $mapped_fields[$type]);
            $schema['fields'][$row->name] = [
                'type' => $type,
                'size' => $size,
                'not null' => !empty($row->notnull) || $row->pk !== "0",
            ];
            if ($length) {
                $schema['fields'][$row->name]['length'] = $length;
            }
            // Convert the default into a properly typed value.
            if ($row->dflt_value === 'NULL') {
                $schema['fields'][$row->name]['default'] = NULL;
            }
            elseif (is_string($row->dflt_value) && $row->dflt_value[0] === '\'') {
                // Remove the wrapping single quotes. And replace duplicate single
                // quotes with a single quote.
                $schema['fields'][$row->name]['default'] = str_replace("''", "'", substr($row->dflt_value, 1, -1));
            }
            elseif (is_numeric($row->dflt_value)) {
                // Adding 0 to a string will cause PHP to convert it to a float or
                // an integer depending on what the string is. For example:
                // - '1' + 0 = 1
                // - '1.0' + 0 = 1.0
                $schema['fields'][$row->name]['default'] = $row->dflt_value + 0;
            }
            else {
                $schema['fields'][$row->name]['default'] = $row->dflt_value;
            }
            // $row->pk contains a number that reflects the primary key order. We
            // use that as the key and sort (by key) below to return the primary key
            // in the same order that it is stored in.
            if ($row->pk) {
                $schema['primary key'][$row->pk] = $row->name;
            }
        }
        else {
            throw new \Exception("Unable to parse the column type " . $row->type);
        }
    }
    ksort($schema['primary key']);
    // Re-key the array because $row->pk starts counting at 1.
    $schema['primary key'] = array_values($schema['primary key']);
    $indexes = [];
    $result = $this->connection
        ->query('PRAGMA ' . $info['schema'] . '.index_list(' . $info['table'] . ')');
    foreach ($result as $row) {
        if (strpos($row->name, 'sqlite_autoindex_') !== 0) {
            $indexes[] = [
                'schema_key' => $row->unique ? 'unique keys' : 'indexes',
                'name' => $row->name,
            ];
        }
    }
    foreach ($indexes as $index) {
        $name = $index['name'];
        // Get index name without prefix.
        $index_name = substr($name, strlen($info['table']) + 1);
        $result = $this->connection
            ->query('PRAGMA ' . $info['schema'] . '.index_info(' . $name . ')');
        foreach ($result as $row) {
            $schema[$index['schema_key']][$index_name][] = $row->name;
        }
    }
    return $schema;
}

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