Snippet Name: BACPAC_Export_External_References
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Created Date: 2025-06-16 13:12:48
Last Modified Date: 2025-05-31 10:31:49
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Title: BACPAC Export External References
Author: user
i have a large azure sql database that features external data sources and external tables. when i try to create a bacpac in the azure portal, i get an error like 'azure bacpac fails "contains an unresolved reference to an object."'
Author: ChatGPT
This error commonly occurs when creating a BACPAC file for databases that include **external data sources** and **external tables** in Azure SQL Database. The issue arises because BACPAC exports do not support **external objects**, which means references to external data sources or tables will be unresolved.
### Steps to Work Around the Error
1. **Exclude External Tables**: You can export the database without external tables. One approach is to **drop the external tables and data sources** before exporting the BACPAC and then recreate them afterward.
2. **Script External Tables and Data Sources**:
- Before dropping the external objects, script out all the **external tables** and **data sources**.
- Use these scripts to recreate the external objects in the destination after importing the BACPAC.
To script out external tables and data sources, you can use SQL Server Management Studio (SSMS) or Azure Data Studio:
- Right-click the external table or external data source.
- Select **Script as CREATE** and save the output.
3. **Create a Custom Export Process**:
- Instead of using a BACPAC, you could export the database using a **custom SQL Server Data Tools (SSDT)** project or **SSMS data export**. This would allow you to manually handle external references while exporting and importing the data.
4. **Use Data Sync or Copy**: You could also use **Azure Data Sync** or **Azure SQL Database Copy** to replicate the database to a new instance and then attempt the BACPAC export on the copy after removing external tables.
Would you like help with scripting the external tables or automating this process?
Author: user
the objective is to copy the azure sql database to a subscript in another role and subscription. i thought Azyre SQL Database Copy can only copy to a server int he same subscription
Author: ChatGPT
You're correct that **Azure SQL Database Copy** can typically only copy a database within the same subscription. However, if your objective is to copy the database to another **Azure subscription** (or role) while preserving the data and schema (excluding unsupported objects like external tables), you have a few alternative methods to achieve this:
### 1. **Export to BACPAC (with Modifications) and Import**
Since BACPAC doesn???t support external objects (like external tables and data sources), follow these steps:
1. **Modify the Source Database**:
- **Script** and **drop** the external tables and external data sources from the database.
- Ensure you save the **scripts** to recreate them later in the destination database.
2. **Export the BACPAC**:
- After dropping the unsupported objects, export the database to a BACPAC using the Azure Portal, **Azure CLI**, or **SSMS**.
3. **Import the BACPAC in the Target Subscription**:
- Upload the BACPAC to **Azure Blob Storage**.
- In the target subscription, import the BACPAC to the new Azure SQL Database.
4. **Recreate the External Objects**:
- Run the saved scripts to recreate the external tables and external data sources in the destination database.
### 2. **Data Migration Using Azure SQL Data Sync**
- **Azure SQL Data Sync** allows you to sync data between two Azure SQL databases, even across subscriptions. While it doesn???t handle schema changes, you can use it to move data after setting up the schema manually.
**Steps**:
1. Create a **Data Sync Group** on the source Azure SQL Database.
2. Set the **target database** (in the new subscription) as a member of the sync group.
3. Perform the sync to move the data.
Note that you???d still need to recreate the external tables and data sources manually, but this method moves data reliably.
### 3. **Generate Scripts for the Schema and Data**
- If you prefer a more manual process, you can **generate scripts** for both schema and data using **SSMS** or **Azure Data Studio**.
**Steps**:
1. **Right-click the database** in SSMS and select **Tasks** > **Generate Scripts**.
2. Choose to script both **schema and data**.
3. Run the scripts in the new Azure SQL Database in the target subscription.
While this method can handle most objects, external data sources still need to be manually recreated in the target database.
### 4. **Use Third-Party Tools** (If Allowed)
- Tools like **Redgate SQL Compare/Data Compare** or **Azure Data Studio Extensions** can compare databases and move both schema and data. However, external tables and data sources will still need manual handling.
Would you prefer any of these methods, or would you like detailed steps on implementing one of them?
Author: user
if i were to use the drop of external tables, do i need to also drop the external source as well? what about teh database scoped credential?
Author: ChatGPT
Yes, if you're going to drop the **external tables**, you should also handle the **external data sources** and **database-scoped credentials**. Here's how each of these objects should be managed when preparing to export the BACPAC:
### 1. **External Tables**:
- **Drop all external tables** first. The external tables depend on the external data source, so these must be removed before dropping the external data source.
- You can use a script like the following to drop all external tables:
```sql
DROP EXTERNAL TABLE [schema_name].[external_table_name];
```
### 2. **External Data Sources**:
- Once the external tables are dropped, you can **drop the external data sources** as well, since BACPAC export does not support them.
- Use the following command to drop an external data source:
```sql
DROP EXTERNAL DATA SOURCE [data_source_name];
```
### 3. **Database-Scoped Credentials**:
- **Database-scoped credentials** are typically associated with external data sources. While they don't necessarily have to be dropped, they should be considered depending on whether they are referenced by any remaining objects (after external tables and data sources are dropped).
If no objects are referencing the database-scoped credentials after external tables and data sources are removed, you can drop the credentials as well:
```sql
DROP DATABASE SCOPED CREDENTIAL [credential_name];
```
If you decide not to drop the database-scoped credentials, you won't be able to reference them in the BACPAC (they won't cause a failure themselves, but the BACPAC may include unnecessary objects). Therefore, it???s recommended to script and drop these credentials to ensure a smooth BACPAC export.
### Suggested Steps:
1. **Script the External Objects**:
- Script the external tables, data sources, and database-scoped credentials before dropping them so you can recreate them later in the target database.
2. **Drop External Tables**:
- Drop the external tables first as they rely on the external data sources.
3. **Drop External Data Sources**:
- Drop the external data sources after the tables.
4. **Drop Database-Scoped Credentials**:
- Finally, drop the database-scoped credentials unless they are needed for any remaining objects.
Once you've done this, proceed with creating the BACPAC, and after restoring the BACPAC in the new subscription, use your saved scripts to recreate the external objects.
Would you like assistance with writing a script to automate dropping and recreating these objects?
Author: user
suppose i wanted to create the equivalent of a bacpac, which contains all the objects, all scripted out, along with their data. is that a feasible exercise? i would also need an executable to playback that object we create
Author: ChatGPT
Yes, creating the equivalent of a BACPAC, which contains **all objects (including external tables, data sources, database-scoped credentials)** and **their data**, is feasible. You can achieve this by generating **SQL scripts** for both the schema and the data, then packaging everything together in a way that allows playback or restoration in the target environment. Here???s a high-level approach to achieve this:
### Step-by-Step Process
#### 1. **Script All Database Objects** (Schema + Data)
You???ll need to generate scripts for **all database objects**, including tables, external tables, procedures, views, external data sources, and credentials.
##### **Using SQL Server Management Studio (SSMS):**
1. **Schema Script**:
- In SSMS, right-click the database.
- Go to **Tasks** > **Generate Scripts**.
- Select **Script entire database and all objects**.
- Choose options to script both **schema and data** for each object type, and make sure external objects are included.
- Save the scripts as files.
2. **Data Export**:
- For each table, including regular and external tables, you can script the **INSERT INTO** statements along with the data. This can be done using the **Generate Scripts** wizard, selecting both schema and data for each table.
- Alternatively, you can export the data using the **SQL Server Import and Export Wizard** or custom `bcp` commands.
##### **Custom Script Generator (SQL/PowerShell/Python)**:
- Write a custom script (e.g., using **T-SQL**, **PowerShell**, or **Python**) to iterate through all objects and export both schema and data into separate files. This can give you more flexibility and control over the structure and content of the export files.
#### 2. **Package the Scripts and Data**
Once the scripts for schema and data are generated, you can package them in a structure that is easy to **playback**.
- **Organize Files**:
- Create folders for different types of objects like `Tables`, `Procedures`, `Views`, `ExternalDataSources`, `Credentials`, etc.
- Within each folder, save individual files for each object type (e.g., `CreateTable_Customers.sql`, `CreateExternalTable_SalesData.sql`, `CreateCredential_AzureBlob.sql`).
- **Compress/Package**:
- Zip all the scripts and data together into a file that can be moved to the target environment.
#### 3. **Executable/Playback Script**
To automate the restoration of the database, you can create an **executable playback script** that runs all the SQL scripts in sequence. Here???s how you can approach that:
##### **Option 1: PowerShell or Bash Script**
Create a script in **PowerShell** (for Windows) or **Bash** (for Linux) to:
1. Connect to the destination SQL Server/Azure SQL Database.
2. Run the scripts in the correct order (first creating objects, then inserting data).
Sample PowerShell script:
```powershell
$server = "your_server_name"
$database = "your_database_name"
$credential = "your_login_credential"
$schemaScripts = Get-ChildItem "C:\Path
Author: user
the query attached generates output with the definition for all external tables. i see it is redundant, where it is checking if the column is sparse or not nullable, but the case is repeated multiple times. can you refactor it to be remove that duplicative case statemetns
Author: tool
All the files uploaded by the user have been fully loaded. Searching won't provide additional information.
Author: ChatGPT
The query in your file contains multiple repetitive `CASE` statements for handling whether a column is sparse or nullable, leading to redundancy. I will refactor the logic to remove these duplications and simplify the `CASE` conditions, focusing on shared logic for sparse and nullable checks.
Here's the refactored query:
```sql
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
GO
DECLARE @MaxObjectLength INT;
SELECT @MaxObjectLength = MAX(LEN(colz.name)) + 2
FROM sys.external_tables AS tabz
INNER JOIN sys.columns AS colz
ON [colz].[object_id] = [tabz].[object_id];
SELECT DISTINCT
SCHEMA_NAME(t.schema_id) AS SchemaName,
t.name AS ObjectName,
sq.Columns,
'IF NOT EXISTS (SELECT * FROM sys.external_tables WHERE name = ''' + t.name + ''' AND schema_id = SCHEMA_ID(''' + SCHEMA_NAME(t.schema_id) + '''))' + CHAR(13) + CHAR(10)
+ 'BEGIN ' + CHAR(13) + CHAR(10)
+ ' CREATE EXTERNAL TABLE ' + QUOTENAME(SCHEMA_NAME(t.schema_id)) + '.' + QUOTENAME(t.name) + CHAR(13) + CHAR(10)
+ ' (' + CHAR(13) + CHAR(10)
+ sq.Columns
+ ' )' + CHAR(13) + CHAR(10)
+ ' WITH ('
+ CASE WHEN t.location IS NOT NULL THEN ' LOCATION = ''' + ISNULL(t.location,'') + ''' ' ELSE '' END + CHAR(13) + CHAR(10)
+ CASE WHEN ds.name IS NOT NULL THEN ' DATA_SOURCE = ' + QUOTENAME(ISNULL(ds.name,'')) ELSE '' END
+ CASE WHEN t.remote_schema_name IS NOT NULL THEN ',SCHEMA_NAME = N''' + t.remote_schema_name + ''',OBJECT_NAME = N''' + t.remote_object_name + '''' ELSE '' END + CHAR(13) + CHAR(10)
+ CASE WHEN ff.name IS NOT NULL THEN ' FILE_FORMAT = ' + QUOTENAME(ff.name) ELSE '' END + CHAR(13) + CHAR(10)
+ ' );' + CHAR(13) + CHAR(10)
+ 'END' AS definition
FROM sys.external_tables t
JOIN (
SELECT object_id,
Columns = STUFF((
SELECT ' '
+ QUOTENAME(sc.name) + SPACE(@MaxObjectLength - LEN(QUOTENAME(sc.name)))
+ TYPE_NAME(sc.system_type_id)
+ CASE
WHEN TYPE_NAME(sc.user_type_id) IN ('decimal', 'numeric')
THEN '(' + CONVERT(VARCHAR, sc.precision) + ',' + CONVERT(VARCHAR, sc.scale) + ')'
WHEN TYPE_NAME(sc.user_type_id) IN ('datetime2', 'datetimeoffset', 'time')
THEN '(' + CONVERT(VARCHAR, sc.scale) + ')'
WHEN TYPE_NAME(sc.user_type_id) IN ('float')
THEN CASE WHEN sc.precision = 53 THEN '' ELSE '(' + CONVERT(VARCHAR, sc.precision) + ')' END
WHEN TYPE_NAME(sc.user_type_id) IN ('char', 'varchar', 'binary', 'varbinary')
THEN CASE WHEN sc.max_length = -1 THEN '(max)' ELSE '(' + CONVERT(VARCHAR, sc.max_length) + ')' END
WHEN TYPE_NAME(sc.user_type_id) IN ('nchar', 'nvarchar')
THEN CASE WHEN sc.max_length = -1 THEN '(max)' ELSE '(' + CONVERT(VARCHAR, (sc.max_length / 2)) + ')' END
ELSE ''
END
+ CASE WHEN sc.is_sparse = 1 THEN ' SPARSE' ELSE '' END
+ CASE WHEN sc.is_nullable = 0 THEN ' NOT NULL' ELSE ' NULL' END
+ CASE WHEN sc.default_object_id <> 0
THEN ' CONSTRAINT ' + QUOTENAME(def.name) + ' DEFAULT ' + ISNULL(def.definition, '')
ELSE ''
END + ',' + CHAR(13) + CHAR(10)
FROM sys.columns sc
LEFT JOIN sys.default_constraints def ON sc.default_object_id = def.object_id AND def.parent_column_id = sc.column_id
WHERE sc.object_id = s.object_id
ORDER BY sc.column_id
FOR XML PATH(''), TYPE).value('.', 'varchar(max)'), 1, 1, '')
FROM sys.columns s
) sq ON t.object_id = sq.object_id
INNER JOIN sys.external_data_sources ds ON t.data_source_id = ds.data_source_id
LEFT JOIN sys.external_file_formats ff ON t.file_format_id = ff.file_format_id
ORDER BY SchemaName, ObjectName;
```
### Key Improvements:
1. **Simplified Data Type Logic**: The `CASE` statements for handling data types (with precision, scale, or max length) have been refactored to avoid repeating similar logic for different types.
2. **Unified Sparse and Nullable Logic**: The `SPARSE` and `NULL/NOT NULL` checks are handled once for all data types instead of being repeated inside individual cases.
3. **Removed Redundant Cases**: By grouping similar checks (such as for `decimal/numeric` or `char/varchar`), the number of `CASE` branches has been significantly reduced.
This refactored query should be more concise and easier to maintain while still generating the necessary SQL definition for external tables. Let me know if you'd like any further adjustments!