How do create Setup/InstallSchema.php in magento2?

Question

I'm tried create Setup/InstallSchema.php in magento2 but it not work. So any so any suggestion? thanks. This file InstallSchema.php

    <?php
/**
 * Copyright © 2015 Magento. All rights reserved.
 * See COPYING.txt for license details.
 */

namespace Xanka\Slider\Setup;

use Magento\Framework\Setup\InstallSchemaInterface;
use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\SchemaSetupInterface;
/**
 * @codeCoverageIgnore
 */
class InstallSchema implements InstallSchemaInterface
{
    /**
     * {@inheritdoc}
     * @SuppressWarnings(PHPMD.ExcessiveMethodLength)
     */
    public function install(SchemaSetupInterface $setup, ModuleContextInterface $context)
    {
        $installer = $setup;

        $installer->startSetup();

        /**
         * Create table 'slideshow'
         */     
        $table = $installer->getConnection()
            ->newTable($installer->getTable('slideshow'))
            ->addColumn(
                'slideshow_id',
                \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
                null,
                ['identity' => true, 'unsigned' => true, 'nullable' => false, 'primary' => true],
                'Slideshow ID'
            )       
            ->addColumn(
                'name',
                \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
                32,
                ['nullable' => false],
                'Name'
            )
            ->addColumn(
                'created_at',
                \Magento\Framework\DB\Ddl\Table::TYPE_TIMESTAMP,
                null,
                [],
                'Creation Time'
            )
            ->addColumn(
                'updated_at',
                \Magento\Framework\DB\Ddl\Table::TYPE_TIMESTAMP,
                null,
                [],
                'Updatetion Time'
            )              
            ->setComment('Slideshow Table');
        $installer->getConnection()->createTable($table);

        /**
         * Create table 'slidewshow_data'
         */
        $table = $installer->getConnection()
            ->newTable($installer->getTable('slideshow_data'))
            ->addColumn(
                'entity_id',
                \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
                null,
                ['identity' => true, 'unsigned' => true, 'nullable' => false, 'primary' => true],
                'Entity ID'
            )
            ->addColumn(
                'slideshow_id',
                \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
                 null,
                 ['nullable' => false],
                'Slideshow ID'
            )
             ->addColumn(
                'name',
                \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
                32,
                ['nullable' => false],
                'Name'
            )
             ->addColumn(
                'image',
                \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
                255,
                ['nullable' => false],
                'Image Url'
            )
             ->addColumn(
                'description',
                \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
                255,
                [],
                'Descripntion'
            )
            ->addColumn(
            'created_time',
            \Magento\Framework\DB\Ddl\Table::TYPE_TIMESTAMP,
                null,
                [],
                'Creation Time'
            )->addColumn(
                'updated_time',
                \Magento\Framework\DB\Ddl\Table::TYPE_TIMESTAMP,
                null,
                [],
                'Modification Time'
            ) 
            ->addIndex(
                $installer->getIdxName('slideshow_data', ['slideshow_id']),
                ['slideshow_id']
            )
            ->addForeignKey(
                $installer->getFkName('slideshow_data', 'slideshow_id', 'slideshow', 'slideshow_id'),
                'slideshow_id',
                $installer->getTable('slideshow'),
                'slideshow_id',
                \Magento\Framework\DB\Ddl\Table::ACTION_CASCADE
            )           
            ->setComment('Slideshow Data Table');                 
        $installer->getConnection() ->createTable($table);
        $installer->endSetup();

    }
}

Answer 1

In Magento 2 setup/update scripts do not run automatic. Please read documentation, how to enable/setup module

Also you may need modify/delete record in setup_module table in case if you need to rerun setup/upgrade script, because magento do not re run in case when the schema_version attribute from module.xml file is exists with same version in this table

Answer 2

To upgrade module we need to create UpgradeSchema.php in Setup folder
1. change the Version in module.xml that is
setup_version="2.0.0" to setup_version="2.0.1"
2. in Setup folder create file called UpgradeSchema.php

<?php

namespace Sugarcode\Test\Setup;

use Magento\Framework\Setup\UpgradeSchemaInterface;
use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\SchemaSetupInterface;
use Magento\Framework\DB\Ddl\Table;

class UpgradeSchema implements UpgradeSchemaInterface
{
    public function upgrade(SchemaSetupInterface $setup, ModuleContextInterface $context)
    {
        $setup->startSetup();
         $tableName = $setup->getTable('testtable');
        if (version_compare($context->getVersion(), '2.0.0') < 0) {
            // Changes here.
        }

        if (version_compare($context->getVersion(), '2.0.1', '<')) {

            // Changes here.
        }
        if (version_compare($context->getVersion(), '2.0.2', '<')) {
              if ($setup->getConnection()->isTableExists($tableName) == true) {
                $connection = $setup->getConnection();
                /* $connection->addColumn(
                    $tableName,
                    'updated_at',
                    ['type' => Table::TYPE_DATETIME,'nullable' => false, 'default' => '', 'afters' => 'created_at'],
                    'Updated At'
                ); */
                $connection->changeColumn(
                    $tableName,
                    'summary',
                    'short_summary',
                    ['type' => Table::TYPE_TEXT, 'nullable' => false, 'default' => ''],
                    'Short Summary'
                );
                // Changes here.
            }
        }
        if (version_compare($context->getVersion(), '2.0.3', '<')) {
              if ($setup->getConnection()->isTableExists($tableName) == true) {
                $connection = $setup->getConnection();

                  // Declare data
                $columns = [
                    'updated_at' => [
                        'type' => Table::TYPE_DATETIME,
                        'nullable' => false,
                        'comment' => 'Updated At',
                        'after' => 'created_at',
                    ],
                ];

                $connection = $setup->getConnection();
                foreach ($columns as $name => $definition) {
                    $connection->addColumn($tableName, $name, $definition);
                }

                // Changes here.
            }
        }
        $setup->endSetup();

    }
}

and then run upgrade command that is

php D:\xampp\htdocs\magento2a\bin\magento setup:upgrade

below are the few important function

public function addColumn($tableName, $columnName, $definition, $schemaName = null)
    public function changeColumn($tableName, $oldColumnName, $newColumnName, $definition, $flushData = false, $schemaName = null)
    public function modifyColumn($tableName, $columnName, $definition, $flushData = false, $schemaName = null)
    public function dropColumn($tableName, $columnName, $schemaName = null)

Answer 3

You haven't written a default value for

->addColumn(
     'slideshow_id',
      \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
       ['nullable' => false],
       'Slideshow ID'
 ) 

in slideshow_data , try changing it to

->addColumn(
     'slideshow_id',
      \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
       null,
       ['nullable' => false],
       'Slideshow ID'
 )