Snowflake - Lookup

Overview

You can use this Snap to look up records in the target Snowflake SQL Server table and returns a selected set of fields for every matched record. The Snap executes one request per multiple input documents to avoid making a request for every input record. The Snap ignores any duplicated lookup condition in the input document stream since it maintains a cache for lookup conditions internally. Queries produced by the Snap have the format:

SELECT [Output fields] FROM [Table name] WHERE
          [C1 = V11 AND C2 = V21 AND...[Cn = Vn1] OR
          [C1 = V12 AND C2 = V22 AND...[Cn = Vn2] OR 
          ......................................  OR
          [Cn = V1n AND Cm = V2m AND...[Cn = Vnm]a

The Snap ignores any duplicated lookup condition in the input document stream since it maintains a cache for lookup conditions internally.

Read-type Snap
Works in Ultra Tasks

Prerequisites

You must have minimum permissions on the database to execute Snowflake Snaps. To understand if you already have them, you must retrieve the current set of permissions. The following commands enable you to retrieve those permissions:

SHOW GRANTS ON DATABASE <database_name>
        SHOW GRANTS ON SCHEMA <schema_name>
        SHOW GRANTS TO USER <user_name>

Security Prererequisites

You must have the following permissions in your Snowflake account to execute this Snap:

Usage (DB and Schema): Privilege to use the database, role, and schema.

The following commands enable minimum privileges in the Snowflake Console:

grant usage on database <database_name> to role <role_name>;
              grant usage on schema <database_name>.<schema_name>;

Learn more about Snowflake privileges: Access Control Privileges.

Internal SQL Commands

This Snap uses the LOOKUP command internally. It queries the database and retrieves a set of rows or defines the set of columns returned by a query.

Known Issues

Because of performance issues, all Snowflake Snaps now ignore the Cancel queued queries when pipeline is stopped or if it fails option for Manage Queued Queries, even when selected. Snaps behave as though the default Continue to execute queued queries when the Pipeline is stopped or if it fails option were selected.

Snap views


View	Description	Examples of upstream and downstream Snaps
Input	Each document should have values for one AND clause in the WHERE statement. Each document in the input view should contain a Map data of key-value entries. Input data may contain values needed to evaluate expressions in the Object type, Output fields, and Conditions properties. If the Pass-though on no lookup match property is unchecked, ensure input data types match column data types in the database table. Otherwise, you may encounter an error message `"Cannot find an input data which is related to the output record ....."`. If the error view is open, all input data in the batch are routed to the error view with the same error information.	JSON Formatter Mapper
Output	The output document includes the corresponding input data under the "original" key. If there are no results from the query, each output field will have a null value. Each document in the output view contains a Map data of key-value entries, where keys are the Output fields property values. The input data that has produced the corresponding output data is also included in the output data under the "original" key.	CSV Parser JSON Parser
Error	Error handling is a generic way to handle errors without losing data or failing the Snap execution. You can handle the errors that the Snap might encounter when running the pipeline by choosing one of the following options from the When errors occur list under the Views tab. The available options are: Stop Pipeline Execution Stops the current pipeline execution when an error occurs. Discard Error Data and Continue Ignores the error, discards that record, and continues with the remaining records. Route Error Data to Error View Routes the error data to an error view without stopping the Snap execution. Learn more about Error handling in Pipelines.

Snap settings

Legend:

Expression icon (): Allows using JavaScript syntax to access SnapLogic Expressions to set field values dynamically (if enabled). If disabled, you can provide a static value. Learn more.
SnapGPT (): Generates SnapLogic Expressions based on natural language using SnapGPT. Learn more.
Suggestion icon (): Populates a list of values dynamically based on your Snap configuration. You can select only one attribute at a time using the icon. Type into the field if it supports a comma-separated list of values.
Upload : Uploads files. Learn more.

Learn more about the icons in the Snap settings dialog.


Field / Field set	Type	Description
Label	String	Required. Specify a unique name for the Snap. Modify this to be more appropriate, especially if there are more than one of the same Snap in the pipeline.
Schema Name	String/Expression	Required. Specify the database schema name. In case it is not defined, then the suggestion for the Table Name retrieves all tables names of all schemas. The property is suggestible and will retrieve available database schemas during suggest values. Note: The values can be passed using the pipeline parameters but not the upstream parameter. Default value: N/A Example: Schema_demo
Table Name	String/Expression	Required. Enter or select the name of the Snowflake SQL table to execute the lookup query. Note: The values can be passed using the Pipeline parameters but not the upstream parameter. Default value: N/A Example: employees_table
Output fields	String/Expression	Enter or select output field names for the Snowflake SQL SELECT statement. Default value: N/A Example: ID
Lookup conditions	Use this field set to enter or select the lookup column name.
Value	String/Expression	Enter or select the JSON path of the lookup column value. The value will be provided by the input data field. Default value: N/A Example: $email
Lookup column name	String/Expression	Specify the lookup conditions are created by using the lookup column name and the lookup column value. Each row will build a condition, such aslookupColumn1 = $inputField. Each additional row will be concatenated using a logical AND. All rows together build the lookup condition being used to look up records in the lookup table. Default value: N/A Example: $email
Pass-through on no lookup match	Checkbox	Required. When there is no lookup matching an input document, the input document will pass through to the output view if this property is checked. Otherwise, it will be written to the error view as an error condition. Default status: deselected
Number of retries	Integer/Expression	Specify the maximum number of retry attempts when the Snap fails to read. Minimum Value: 0 Default value: 0 Example: 3
Retry interval (seconds)	Integer/Expression	Specifies the minimum number of seconds the Snap must wait before each retry attempt. Minimum Value: 1 Default value: 1 Example: 3
Input Date Format	Dropdown list	The property has the following two options: Select Continue to execute the snap with the given input Date format if you want the Snap to continue with the current date format. This option is selected by default. Select Auto Convert the format to Snowflake default format if you want the Snap to convert the provided date format to the default Snowflake date format. To know about the date formats supported by Snowflake, see Snowflake date formats Default value: Continue to execute the snap with given input Date format Example: Auto Convert the format to Snowflake default format
Handle Timestamp and Date Time Data	Dropdown list	Choose an option for handling timestamp and date time data. The available options are: Default Date Time format in UTC Time Zone: The Snowflake date time data are represented in UTC Time Zone. SnapLogic Date Time format in Regional Time Zone: The Snowflake date time data are represented in the same regional time zone value, as provided in the Snowflake account. Note: Recommendation: If you use the Timestamp TZ and Timestamp LTZ in this Snap, we recommend you to use SnapLogic Date Time format in Regional TimeZone to ensure that you get the Timestamp data output of the target table in the same format as in the source table. Source Table Target Table
Manage Queued Queries	Dropdown list	Default value: Select an option to determine whether the Snap should continue or cancel the execution of the queued Snowflake Execute SQL queries when you stop the pipeline. Note: If you select Cancel queued queries when the pipeline is stopped or if it fails, then the read queries under execution are canceled, whereas the write type of queries under execution are not canceled. Snowflake internally determines which queries are safe to be canceled and cancels those queries. Default value: Continue to execute queued queries when the Pipeline is stopped or if it fails Example: Cancel queued queries when the pipeline is stopped or if it fails
Snap execution	Dropdown list	Choose one of the three modes in which the Snap executes. Available options are: Validate & Execute: Performs limited execution of the Snap and generates a data preview during pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during pipeline runtime. Execute only: Performs full execution of the Snap during pipeline execution without generating preview data. Disabled: Disables the Snap and all Snaps that are downstream from it. Default value: Execute only Example: Validate & Execute