Delta rewrite URL CE step not using database prefix correctly (with fix)

Nobody has claimed this yet.

### Preconditions

1. Data Migration Completed to or from a site that uses a database prefix
2. Source prefix is different than destination prefix (or only one has a prefix)

### Steps to reproduce

1. Run Delta step after there have been some changes

### Expected result

1. Should run to completion as it did after migration

### Actual result

1. Stops at Rewrites step with error

SQLSTATE[42S02]: Base table or view not found: 1146 Table 'catalog_url_rewrite_product_category' doesn't exist, query was: SELECT `catalog_url_rewrite_product_category`.* FROM `catalog_url_re
write_product_category` WHERE (url_rewrite_id = '9088576') AND (category_id = '27') AND (product_id = '727')

The code complained about does NOT use the prefix as set up in the config

Strangely the delta step had run successfully before so I assume this step is not always run

### Solution

My guess is that in the file `Migration/Step/UrlRewrite/Version191to2000Delta.php`, function `saveProductCategoryRecord` on line 150 the whole block needs a look

`

$select = $this->destination->getAdapter()->getSelect();

$select->from(Version191to2000::DESTINATION_PRODUCT_CATEGORY)
->where('url_rewrite_id = ?', $record->getValue('url_rewrite_id'))
->where('category_id = ?', $record->getValue('category_id'))
->where('product_id = ?', $record->getValue('product_id'));

if (!$this->destination->getAdapter()->loadDataFromSelect($select)) {
$this->destination->saveRecords(
$this->source->addDocumentPrefix(Version191to2000::DESTINATION_PRODUCT_CATEGORY),
[[
'url_rewrite_id' => $record->getValue('url_rewrite_id'),
'category_id' => $record->getValue('category_id'),
'product_id' => $record->getValue('product_id')
]],
true
);
}
`

- line 151 is not using `$this->source->addDocumentPrefix` and it should
- as the select object is `$this->destination` I assume it should be `$select->from($this->destination->addDocumentPrefix(Version191to2000::DESTINATION_PRODUCT_CATEGORY),'*')`
- after fixing this the next command then errors again, as it uses `$this->source->addDocumentPrefix` to insert into the destination, which fails if they are not the same.

so this is what it should be, I think?

`

$select->from($this->destination->addDocumentPrefix(Version191to2000::DESTINATION_PRODUCT_CATEGORY),'*')
->where('url_rewrite_id = ?', $record->getValue('url_rewrite_id'))
->where('category_id = ?', $record->getValue('category_id'))
->where('product_id = ?', $record->getValue('product_id'));

if (!$this->destination->getAdapter()->loadDataFromSelect($select)) {
$this->destination->saveRecords(
$this->destination->addDocumentPrefix(Version191to2000::DESTINATION_PRODUCT_CATEGORY),
[[
'url_rewrite_id' => $record->getValue('url_rewrite_id'),
'category_id' => $record->getValue('category_id'),
'product_id' => $record->getValue('product_id')
]],
true
);
}
`

**THEN you get a similar error for `saveCmsPageRewrites`**

I think
` $adapter->delete(Version191to2000::DESTINATION, "entity_type = 'cms-page'");`

needs document prefix too

See below for fixes successfully made on my one instance

Start in Migration/Step/UrlRewrite/Version191to2000Delta.php, especially saveProductCategoryRecord and saveCmsPageRewrites, and trace how source and destination document prefixes are applied. Reproduce a Delta migration where the source and destination prefixes differ. Done means the Rewrites step completes without missing-table errors, including CMS page rewrites.

Written by the indexing model from the issue text.