Microsoft Azure Synapse SQL Connector

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Microsoft Azure Synapse SQL lookups in mappings

Microsoft Azure Synapse SQL
lookups in mappings

Use a Lookup transformation to retrieve data based on a specified lookup condition.

Use a

Microsoft Azure Synapse SQL

Lookup transformation to look up data in a

Microsoft Azure Synapse SQL

object. For example, the source table includes the customer code, but you want to include the customer name in the target table to make summary data easy to read.

You can use the

Microsoft Azure Synapse SQL

Lookup transformation to look up the customer name in another

Microsoft Azure Synapse SQL

object.

You can also set the default column value for the return field in a cached Lookup transformation in a Microsoft Azure Synapse SQL mapping.

However, in advanced mode, you can't set the default column value for the return field.

You can create the following lookups when you configure field mappings in a mapping task:

Connected with cached or uncached

Unconnected lookup

Connected lookup with dynamic lookup cache

You cannot configure a connected or unconnected uncached lookup for mappings in advanced mode.

The following table describes the

Microsoft Azure Synapse SQL

lookup object properties that you can configure in a Lookup transformation:

Property	Description
Connection	Name of the lookup connection. You can select an existing connection, create a new connection, or define parameter values for the lookup connection property. If you want to overwrite the parameter at runtime, select the Allow parameter to be overridden at run time option when you create a parameter. When the task runs, the agent uses the parameters from the file that you specify in the task advanced session properties. You can switch between a non-parameterized and a parameterized Microsoft Azure Synapse SQL connection. When you switch between the connections, the advanced property values are retained.
Source Type	Type of the source object. Select Single Object, Query, or Parameter. You cannot use custom query as the source type in cached and dynamic cache lookups.
Lookup Object	Name of the lookup object for the mapping.
Parameter	A parameter file where you define values that you want to update without having to edit the task. Select an existing parameter for the lookup object or click New Parameter to define a new parameter for the lookup object. The Parameter property appears only if you select parameter as the source type. If you want to overwrite the parameter at runtime, select the Allow parameter to be overridden at run time option when you create a parameter. When the task runs, the agent uses the parameters from the file that you specify in the task advanced session properties.
Define Query	If the source type is a query, displays the Edit Custom Query dialog box. Enter a valid custom query and click OK .
Multiple Matches	The behavior when the lookup condition returns multiple matches. Select one of the following options: Return first row¹ Return last row¹ Return any row Return all rows Report error If the lookup table has an IDENTITY column, the data for the first row and last row is returned based on the sorting of the IDENTITY column. If the matched rows have duplicates then the values returned are random.
¹Doesn't apply to mappings in advanced mode.

You cannot use Binary, Varbinary, and Datetimeoffset datatypes columns as lookup conditions.

When you use a cached lookup with

Microsoft Azure Synapse SQL

connection and if the lookup condition contains a NULL value, the lookup condition is ignored.

The following table describes the

Microsoft Azure Synapse SQL

lookup advanced properties that you can configure in a Lookup transformation:

Property	Description
Azure Blob Container Name	Required if you select Azure Blob storage in the connection properties. The name of the container in Microsoft Azure Blob Storage. The container name must not contain special characters.
ADLS FileSystem Name	Required if you select ADLS Gen2 storage in the connection properties. The name of the file system in Microsoft Azure Data Lake Storage Gen2. The file system name must not contain special characters. You can also specify the path of the directory under the file system. Use only a forward slash to specify the directory path.
Schema Name Override	Overrides the schema specified in the connection.
Table Name Override	Overrides the table name of the imported Microsoft Azure Synapse SQL source table.
Field Delimiter	Character used to separate fields in the file. Default is 0x1e . You can specify 'TAB' or 0-256 single-char printable and non-printable ASCII characters. Non-printable characters must be specified in hexadecimal. Multi-char ASCII characters except TAB are not applicable. You cannot use the following non-printable characters: 00x0 , 0x0 , 0x0A , 0x1B , 0x0D , and 0x1F
Number of Concurrent Connections to Blob Store¹	Number of concurrent connections to extract data from the Microsoft Azure Blob Storage. When reading a large-size blob, you can spawn multiple threads to process data. Configure Blob Part Size to partition a large-size blob into smaller parts. Default is 4. Maximum is 10.
Blob Part Size¹	Partitions a blob into smaller parts each of specified part size. When reading a large-size blob, consider partitioning the blob into smaller parts and configure concurrent connections to spawn required number of threads to process data in parallel. Default is 8 MB.
Pre-SQL	Pre-SQL command that must be run before reading data from the source.
Post-SQL	Post-SQL command that must be run after reading data from the source.
SQL Override	When you read data from a Microsoft Azure Synapse SQL object, you can configure SQL overrides and define constraints.
On Pre-Post SQL Error	Determines the behavior when a task that includes pre-SQL or post-SQL commands encounters errors. You can select any of the following options: Continue. The task continues regardless of errors. Stop. The task stops when errors occur while executing pre-SQL or post-SQL commands.
Quote Character	The Secure Agent skips the specified character when you read data from Microsoft Azure Synapse SQL . Default is 0x1f .
Interim Directory¹	Optional. Path to the staging directory in the Secure Agent machine. Specify the staging directory where you want to stage the files when you read data from Microsoft Azure Synapse SQL . Ensure that the directory has sufficient space and you have write permissions to the directory. Default staging directory is /tmp . You cannot specify an interim directory when you use the Hosted Agent.
Tracing Level¹	Sets the amount of detail that appears in the log file. You can choose terse, normal, verbose initialization, or verbose data. Default is normal.
Lookup Data Filter¹	Limits the number of lookups that the mapping performs on the cache of the lookup source table based on the value you specify in the filter condition. This property is applicable when you select object as the source type and enable lookup cache on the Advanced tab for the Lookup transformation. Maximum length is 32768 characters. For more information about this property, see Transformations in the Data Integration documentation.
¹Doesn't apply to mappings in advanced mode.