Astera Data Stack
Version 10
Version 10
  • Welcome to Astera Data Stack Documentation
  • RELEASE NOTES
    • Astera 10.5 - Release Notes
    • Astera 10.4 - Release Notes
    • Astera 10.3 - Release Notes
    • Astera 10.2 – Release Notes
    • Astera 10.1 - Additional Notes
    • Astera 10.1 - Release Notes
    • Astera 10.0 - Release Notes
  • SETTING UP
    • System Requirements
    • Product Architecture
    • Migrating from Astera 9 to Astera 10
    • Migrating from Astera 7.x to Astera 10
    • Installing Client and Server Applications
    • Connecting to an Astera Server using the Client
    • How to Connect to a Different Astera Server from the Client
    • How to Build a Cluster Database and Create Repository
    • Repository Upgrade Utility in Astera
    • How to Login from the Client
    • How to Verify Admin Email
    • Licensing in Astera
    • How to Supply a License Key Without Prompting the User
    • Install Manager
    • User Roles and Access Control
      • Windows Authentication
      • Azure Authentication
    • Offline Activation of Astera
    • Setting Up R in Astera
    • Silent Installation
  • DATAFLOWS
    • What are Dataflows?
    • Sources
      • Data Providers and File Formats Supported in Astera Data Stack
      • Setting Up Sources
      • Excel Workbook Source
      • COBOL File Source
      • Database Table Source
      • Delimited File Source
      • File System Items Source
      • Fixed Length File Source
      • Email Source
      • Report Source
      • SQL Query Source
      • XML/JSON File Source
      • PDF Form Source
      • Parquet File Source (Beta)
      • MongoDB Source (Beta)
      • Data Model Query
    • Transformations
      • Introducing Transformations
      • Aggregate Transformation
      • Constant Value Transformation
      • Denormalize Transformation
      • Distinct Transformation
      • Expression Transformation
      • Filter Transformation
      • Join Transformation
      • List Lookup Transformation
      • Merge Transformation
      • Normalize Transformation
      • Passthru Transformation
      • Reconcile Transformation
      • Route Transformation
      • Sequence Generator
      • Sort Transformation
      • Sources as Transformations
      • Subflow Transformation
      • Switch Transformation
      • Tree Join Transformation
      • Tree Transform
      • Union Transformation
      • Data Cleanse Transformation
      • File Lookup Transformation
      • SQL Statement Lookup
      • Database Lookup
      • AI Match Transformation
    • Destinations
      • Setting Up Destinations
      • Database Table Destination
      • Delimited File Destination
      • Excel Workbook Destination
      • Fixed Length File Destination
      • SQL Statement Destination
      • XML File Destination
      • Parquet File Destination (Beta)
      • Excel Workbook Report
      • MongoDB Destination
    • Data Logging and Profiling
      • Creating Data Profile
      • Creating Field Profile
      • Data Quality Mode
      • Using Data Quality Rules in Astera
      • Record Level Log
      • Quick Profile
    • Database Write Strategies
      • Data Driven
      • Source Diff Processor
      • Database Diff Processor
    • Text Processors
      • Delimited Parser
      • Delimited Serializer
      • Language Parser
      • Fixed Length Parser
      • Fixed Length Serializer
      • XML/JSON Parser
      • XML/JSON Serializer
    • Data Warehouse
      • Fact Table Loader
      • Dimension Loader
      • Data Vault Loader
    • Testing and Diagnostics
      • Correlation Analysis
    • Visualization
      • Basic Plots
      • Distribution Plots
    • EDI
      • EDI Source File
      • EDI Message Parser
      • EDI Message Serializer
      • EDI Destination File
  • WORKFLOWS
    • What are Workflows?
    • Creating Workflows in Astera
    • Decision
    • EDI Acknowledgment
    • File System
    • File Transfer
      • FTP
      • SFTP
    • Or
    • Run Dataflow
    • Run Program
    • Run SQL File
    • Run SQL Script
    • Run Workflow
    • Send Mail
    • Workflows with a Dynamic Destination Path
    • Customizing Workflows With Parameters
    • GPG-Integrated File Decryption in Astera
    • AS2
      • Setting up an AS2 Server
      • Adding an AS2 Partner
      • AS2 Workflow Task
  • Subflows
    • Using Subflows in Astera
  • DATA MODEL
    • Creating a Data Warehousing Project
    • Data Models
      • Introducing Data Models
      • Opening a New Data Model
      • Data Modeler - UI Walkthrough
      • Reverse Engineering an Existing Database
      • Creating a Data Model from Scratch
      • General Entity Properties
      • Creating and Editing Relationships
      • Relationship Manager
      • Virtual Primary Key
      • Virtual Relationship
      • Change Field Properties
      • Forward Engineering
      • Verifying a Data Model
    • Dimensional Modelling
      • Introducing Dimensional Models
      • Converting a Data Model to a Dimensional Model
      • Build Dimensional Model
      • Fact Entities
      • Dimension Entities
      • Placeholder Dimension for Early Arriving Facts and Late Arriving Dimensions
      • Date and Time Dimension
      • Aggregates in Dimensional Modeling
      • Verifying a Dimensional Model
    • Data Vaults
      • Introducing Data Vaults
      • Data Vault Automation
      • Raw Vault Entities
      • Bridge Tables
      • Point-In-Time Tables
    • Documentation
      • Generating Technical and Business Documentation for Data Models
      • Lineage and Impact Analysis
    • Deployment and Usage
      • Deploying a Data Model
      • View Based Deployment
      • Validate Metadata and Data Integrity
      • Using Astera Data Models in ETL Pipelines
      • Connecting an Astera Data Model to a Third-Party Visualization Tool
  • REPORT MODEL
    • User Guide
      • Report Model Tutorial
    • Report Model Interface
      • Report Options
      • Report Browser
      • Data Regions in Report Models
      • Region Properties Panel
      • Pattern Properties
      • Field Properties Panel
    • Use Cases
      • Auto-Creating Data Regions and Fields
      • Line Count
      • Auto-Parsing
      • Pattern Count
      • Applying Pattern to Line
      • Regular Expression
      • Floating Patterns and Floating Fields
      • Creating Multi-Column Data Regions
      • Defining the Start Position of Data Fields
      • Data Field Verification
      • Using Comma Separated Values to Define Start Position
      • Defining Region End Type as Specific Text and Regular Expression
      • How To Work With PDF Scaling Factor in a Report Model
      • Connecting to Cloud Storage
    • Auto Generate Layout
      • Setting Up AGL in Astera
      • UI Walkthrough - Auto Generation of Layout, Fields and Table
      • Using Auto Generation Layout, Auto Create Fields and Auto Create Table (Preview)
    • AI Powered Data Extraction
      • AI Powered Data Extraction Using Astera North Star
      • Best Practices for AI-Powered Template Creation in Astera
    • Optical Character Recognition
      • Loading PDFs with OCR
      • Best Practices for OCR Usage
    • Exporting Options
      • Exporting a Report Model
      • Exporting Report Model to a Dataflow
    • Miscellaneous
      • Importing Monarch Models
      • Microsoft Word and Rich Text Format Support
      • Working With Problematic PDF Files
  • API Flow
    • API Publishing
      • Develop
        • Designing an API Flow
        • Request Context Parameters
        • Configuring Sorting and Filtering in API Flows
        • Enable Pagination
        • Asynchronous API Request
        • Multiple Responses using Conditional Route
        • Workflow Tasks in an API Flow
        • Enable File Download-Upload Through APIs
        • Database CRUD APIs Auto-Generation
        • Pre-deployment Testing and Verification of API flows
        • Multipart/Form-Data
        • Certificate Store
      • Publish
        • API Deployment
        • Test Flow Generation
      • Manage
        • Server Browser Functionalities for API Publishing
          • Swagger UI for API Deployments
        • API Monitoring
        • Logging and Tracing
    • API Consumption
      • Consume
        • API Connection
        • Making API Calls with the API Client
        • API Browser
          • Type 1 – JSON/XML File
          • Type 2 – JSON/XML URL
          • Type 3 – Import Postman API Collections
          • Type 4 - Create or customize API collection
          • Pre-built Custom Connectors
        • Request Service Options - eTags
        • HTTP Redirect Calls
        • Method Operations
        • Pagination
        • Raw Preview And Copy Curl Command
        • Support for text/XML and SOAP Protocol
        • API Logging
        • Making Multipart/Form-Data API Calls
      • Authorize
        • Open APIs - Configuration Details
        • Authorizing Facebook APIs
        • Authorizing Astera’s Server APIs
        • Authorizing Avaza APIs
        • Authorizing the Square API
        • Authorizing the ActiveCampaign API
        • Authorizing the QuickBooks’ API
        • Astera’s Server API Documentation
        • NTLM Authentication
        • AWS Signature Authentication
        • Accessing Astera’s Server APIs Through a Third-Party Tool
          • Workflow Use Case
  • Project Management and Scheduling
    • Project Management
      • Deployment
      • Server Monitoring and Job Management
      • Cluster Monitor and Settings
      • Connecting to Source Control
      • Astera Project and Project Explorer
      • CAR Convert Utility Guide
    • Job Scheduling
      • Scheduling Jobs on the Server
      • Job Monitor
    • Configuring Multiple Servers to the Same Repository (Load Balancing)
    • Purging the Database Repository
  • Data Governance
    • Deployment of Assets in Astera Data Stack
    • Logging In
    • Tags
    • Modifying Asset Details
    • Data Discoverability
    • Data Profile
    • Data Quality
    • Scheduler
    • Access Management
  • Functions
    • Introducing Function Transformations
    • Custom Functions
    • Logical
      • Coalesce (Any value1, Any value2)
      • IsNotNull (AnyValue)
      • IsRealNumber (AnyValue)
      • IsValidSqlDate (Date)
      • IsDate (AnyValue)
      • If (Boolean)
      • If (DateTime)
      • If (Double)
      • Exists
      • If (Int64)
      • If (String)
      • IsDate (str, strformat)
      • IsInteger (AnyValue)
      • IsNullOrWhitespace (StringValue)
      • IsNullorEmpty (StringValue)
      • IsNull (AnyValue)
      • IsNumeric (AnyValue)
    • Conversion
      • GetDateComponents (DateWithOffset)
      • ParseDate (Formats, Str)
      • GetDateComponents (Date)
      • HexToInteger (Any Value)
      • ToInteger (Any value)
      • ToDecimal (Any value)
      • ToReal (Any value)
      • ToDate (String dateStr)
      • TryParseDate (String, UnknownDate)
      • ToString (Any value)
      • ToString (DateValue)
      • ToString (Any data, String format)
    • Math
      • Abs (Double)
      • Abs (Decimal)
      • Ceiling (Real)
      • Ceiling(Decimal)
      • Floor (Decimal)
      • Floor (Real)
      • Max (Decimal)
      • Max (Date)
      • Min (Decimal)
      • Min (Date)
      • Max (Real)
      • Max (Integer)
      • Min (Real)
      • Pow (BaseExponent)
      • Min (Integer)
      • RandomReal (Int)
      • Round (Real)
      • Round (Real Integer)
      • Round (Decimal Integer)
      • Round (Decimal)
    • Financial
      • DDB
      • FV
      • IPmt
      • IPmt (FV)
      • Pmt
      • Pmt (FV)
      • PPmt
      • PPmt (FV)
      • PV (FV)
      • Rate
      • Rate (FV)
      • SLN
      • SYD
    • String
      • Center (String)
      • Chr (IntAscii)
      • Asc (String)
      • AddCDATAEnvelope
      • Concatenate (String)
      • ContainsAnyChar (String)
      • Contains (String)
      • Compact (String)
      • Find (Int64)
      • EndsWith (String)
      • FindIntStart (Int32)
      • Extract (String)
      • GetFindCount (Int64)
      • FindLast (Int64)
      • GetDigits (String)
      • GetLineFeed
      • Insert (String)
      • IsAlpha
      • GetToken
      • IndexOf
      • IsBlank
      • IsLower
      • IsUpper
      • IsSubstringOf
      • Length (String)
      • LeftOf (String)
      • Left (String)
      • IsValidName
      • Mid (String)
      • PadLeft
      • Mid (String Chars)
      • LSplit (String)
      • PadRight
      • ReplaceAllSpecialCharsWithSpace
      • RemoveChars (String str, StringCharsToRemove)
      • ReplaceLast
      • RightAlign
      • Reverse
      • Right (String)
      • RSplit (String)
      • SplitStringMultipleRecords
      • SplitStringMultipleRecords (2 Separators)
      • SplitString (3 separators)
      • SplitString
      • SplitStringMultipleRecords (3 Separators)
      • Trim
      • SubString (NoOfChars)
      • StripHtml
      • Trim (Start)
      • TrimExtraMiddleSpace
      • TrimEnd
      • PascalCaseWithSpace (String str)
      • Trim (String str)
      • ToLower(String str)
      • ToProper(String str)
      • ToUpper (String str)
      • Substring (String str, Integer startAt)
      • StartsWith (String str, String value)
      • RemoveAt (String str, Integer startAt, Integer noofChars)
      • Proper (String str)
      • Repeat (String str, Integer count)
      • ReplaceAll (String str, String lookFor, String replaceWith)
      • ReplaceFirst (String str, String lookFor, String replaceWith)
      • RightOf (String str, String lookFor)
      • RemoveChars (String str, String charsToRemove)
      • SplitString (String str, String separator1, String separator2)
    • Date Time
      • AddMinutes (DateTime)
      • AddDays (DateTimeOffset)
      • AddDays (DateTime)
      • AddHours (DateTime)
      • AddSeconds (DateTime)
      • AddMonths (DateTime)
      • AddMonths (DateTimeOffset)
      • AddMinutes (DateTimeOffset)
      • AddSeconds (DateTimeOffset)
      • AddYears (DateTimeOffset)
      • AddYears (DateTime)
      • Age (DateTime)
      • Age (DateTimeOffset)
      • CharToSeconds (Str)
      • DateDifferenceDays (DateTimeOffset)
      • DateDifferenceDays (DateTime)
      • DateDifferenceHours (DateTimeOffset)
      • DateDifferenceHours (DateTime)
      • DateDifferenceMonths (DateTimeOffset)
      • DateDifferenceMonths (DateTime)
      • DatePart (DateTimeOffset)
      • DatePart (DateTime)
      • DateDifferenceYears (DateTimeOffset)
      • DateDifferenceYears (DateTime)
      • Month (DateTime)
      • Month (DateTimeOffset)
      • Now
      • Quarter (DateTime)
      • Quarter (DateTimeOffset)
      • Second (DateTime)
      • Second (DateTimeOffset)
      • SecondsToChar (String)
      • TimeToInteger (DateTime)
      • TimeToInteger (DateTimeOffset)
      • ToDate Date (DateTime)
      • ToDate DateTime (DateTime)
      • ToDateString (DateTime)
      • ToDateTimeOffset-Date (DateTimeOffset)
      • ToDate DateTime (DateTimeOffset)
      • ToDateString (DateTimeOffset)
      • Today
      • ToLocal (DateTime)
      • ToJulianDate (DateTime)
      • ToJulianDayNumber (DateTime)
      • ToTicks (Date dateTime)
      • ToTicks (DateTimeWithOffset dateTime)
      • ToUnixEpoc (Date dateTime)
      • ToUtc (Date dateTime)
      • UnixTimeStampToDateTime (Real unixTimeStamp)
      • UtcNow ()
      • Week (Date dateTime)
      • Week (DateTimeWithOffset dateTime)
      • Year (Date dateTime)
      • Year (DateTimeWithOffset dateTime)
      • DateToJulian (Date dateTime, Integer length)
      • DateTimeOffsetUtcNow ()
      • DateTimeOffsetNow ()
      • Day (DateTimeWithOffset dateTime)
      • Day (Date dateTime)
      • DayOfWeekStr (DateTimeWithOffset dateTime)
      • DayOfWeek (DateTimeWithOffset dateTime)
      • DayOfWeek (Date dateTime)
      • DateToJulian (DateTimeWithOffset dateTime, Integer length)
      • DayOfWeekStr (Date dateTime)
      • FromJulianDate (Real julianDate)
      • DayOfYear (Date dateTime)
      • DaysInMonth(Integer year, Integer month)
      • DayOfYear (DateTimeWithOffset dateTime)
      • FromUnixEpoc
      • FromJulianDayNumber (Integer julianDayNumber)
      • FromTicksUtc(Integer ticks)
      • FromTicksLocal(Integer ticks)
      • Hour (Date dateTime)
      • Hour (DateTimeWithOffset dateTime)
      • Minute (Date dateTime)
      • JulianToDate (String julianDate)
      • Minute (DateTimeWithOffset dateTime)
      • DateToIntegerYYYYMMDD (DateTimeWithOffset dateTime)
      • DateToIntegerYYYYMMDD (Date dateTime)
    • Files
      • AppendTextToFile (String filePath, String text)
      • CopyFile (String sourceFilePath, String destFilePath, Boolean overWrite)
      • CreateDateTime (String filePath)
      • DeleteFile (String filePath)
      • DirectoryExists (String filePath)
      • FileExists (String filePath)
      • FileLength (String filePath)
      • FileLineCount (String filePath)
      • GetDirectory (String filePath)
      • GetEDIFileMetaData (String filePath)
      • GetExcelWorksheets (String excelFilePath)
      • GetFileExtension (String filePath)
      • GetFileInfo (String filePath)
      • GetFileName (String filePath)
      • GetFileNameWithoutExtension (String filePath)
      • LastUpdateDateTime (String filePath)
      • MoveFile (String filePath, String newDirectory)
      • ReadFileBytes (String filePath)
      • ReadFileFirstLine (String filePath)
      • ReadFileText (String filePath)
      • ReadFileText (String filePath, String codePage)
      • WriteBytesToFile (String filePath, ByteArray bytes)
      • WriteTextToFile (String filePath, String text)
    • Date Time With Offset
      • ToDateTimeOffsetFromDateTime (dateTime String)
      • ToUtc (DateTimeWithOffset)
      • ToDateTimeOffsetFromDateTime
      • ToDateTimeOffset (String dateTimeOffsetStr)
      • ToDateTimeFromDateTimeOffset
    • GUID
      • NewGuid
    • Encoding
      • ToBytes
      • FromBytes
      • UrlEncode
      • UrlDecode
      • ComputeSHA256
      • ComputeMD5
      • ComputeHash (Str, Key)
      • ComputeHash (Str, Key, hex)
      • ConvertEncoding
    • Regular Expressions
      • ReplaceRegEx
      • ReplaceRegEx (Integer StartAt)
      • IsMatchRegEx (StartAt)
      • IsMatchRegEx
      • IsUSPhone
      • IsUSZipCode
      • GetMatchRegEx
      • GetMatchRegEx (StartAt)
    • TimeSpan
      • Minutes
      • Hours
      • Days
      • Milliseconds
      • TotalMilliseconds
      • TimeSpanFromTicks
      • Ticks
      • TotalHours
      • Seconds
      • TotalDays
      • ToTimeSpan (Hours, Min, Sec)
      • ToTimeSpan (Milli)
      • ToTimeSpan
      • TotalSeconds
      • TotalMinutes
    • Matching
      • Soundex
      • DoubleMetaphone
      • RefinedSoundex
    • Processes
      • TerminateProcess
      • IsProcessRunning
  • USE CASES
    • End-to-End Use Cases
      • Data Integration
        • Using Astera Data Stack to Create and Orchestrate an ETL Process for Partner Onboarding
      • Data Warehousing
        • Building a Data Warehouse – A Step by Step Approach
      • Data Extraction
        • Reusing The Extraction Template for Similar Layout Files
  • CONNECTORS
    • Setting Up IBM DB2/iSeries Connectivity in Astera
    • Connecting to SAP HANA Database
    • Connecting to MariaDB Database
    • Connecting to Salesforce Database
    • Connecting to Salesforce – Legacy Database
    • Connecting to Vertica Database
    • Connecting to Snowflake Database
    • Connecting to Amazon Redshift Database
    • Connecting to Amazon Aurora Database
    • Connecting to Google Cloud SQL in Astera
    • Connecting to MySQL Database
    • Connecting to PostgreSQL in Astera
    • Connecting to Netezza Database
    • Connecting to Oracle Database
    • Connecting to Microsoft Azure Databases
    • Amazon S3 Bucket Storage in Astera
    • Connecting to Amazon RDS Databases
    • Microsoft Azure Blob Storage in Astera
    • ODBC Connector
    • Microsoft Dynamics CRM
    • Connection Details for Azure Data Lake Gen 2 and Azure Blob Storage
    • Configuring Azure Data Lake Gen 2
    • Connecting to Microsoft Message Queue
    • Connecting to Google BigQuery
    • Azure SQL Server Configuration Prerequisites
    • Connecting to Microsoft Azure SQL Server
    • Connecting to Microsoft SharePoint in Astera
  • Incremental Loading
    • Trigger Based CDC
    • Incremental CDC
  • MISCELLANEOUS
    • Using Dynamic Layout & Template Mapping in Astera
    • Synonym Dictionary File
    • SmartMatch Feature
    • Role-Based Access Control in Astera
    • Updating Your License in Astera
    • Using Output Variables in Astera
    • Parameterization
    • Connection Vault
    • Safe Mode
    • Context Information
    • Using the Data Source Browser in Astera
    • Pushdown Mode
    • Optimization Scenarios
    • Using Microsoft’s Modern Authentication Method in Email Source Object
    • Shared Actions
    • Data Formats
    • AI Automapper
    • Resource Catalog
    • Cloud Deployment
      • Deploying Astera Data Stack on Microsoft Azure Cloud
      • Deploying Astera Data Stack on Oracle Cloud
      • Deploying Astera Data Stack on Amazon Web Services
      • Setting up the Astera Server on AKS
    • GIT In Astera Data Stack
      • GIT Repositories in Astera Data Stack
      • Moving a Repository to a Remote Server
      • Git Conflicts in Astera Data Stack
    • Astera Best Practices
  • FAQs
    • Installation
      • Why do we need to make two installations for Astera?
      • What’s the difference between Custom and Complete installation?
      • What’s the difference between 32-bit and 64-bit Astera?
      • Can we use a single license for multiple users?
      • Does Astera client work when it’s not connected to the server?
      • Why do we need to build a cluster database and set up a repository while working with Astera?
      • How do we set up multiple servers for load balancing?
      • How do we maintain schedules when migrating server or upgrading version?
      • Which database providers does Astera support for setting up a cluster database?
      • How many Astera clients can be connected to a single server?
      • Why is Astera not able to access my source file or create a new one?
    • Sources
      • Can I use data from unstructured documents in dataflows?
      • Can I extract data from fillable PDF forms in Astera?
      • Does Astera support extraction of data residing in online sources?
      • How do I process multiple files in a directory with a single execution of a flow?
      • Can I write information from the File System Items Source to the destination?
      • Can I split a source file into multiple files based on record count?
      • Does Astera support data extraction from unstructured docs or text files?
      • What is the difference between full and incremental loading in database sources?
      • How is the File System Items Source used in a Dataflow?
      • How does the PDF Form Source differ from the Report Source in Astera?
      • Does Astera support extraction of data from EDI files?
      • How does the Raw Text Filter option work in file sources in Astera?
    • Destinations
      • If I want to have a different field delimiter, say a pipe (“|”), is there an option to export with a
      • Tools Menu > Data Format has different date formats, but it doesn’t seem to do anything.
      • Can we export the Object Path column present in the Data Preview window?
      • I want to change the output format of a column.
      • What will be the outcome if we write files multiple times to the same Excel Destination?
    • Transformations
      • How is the Aggregate Transformation different from the Expression Transformation?
      • Can we omit duplicate records using the Aggregate Transformation in Astera?
      • How many datasets can a single Aggregate object take input from?
      • How is Expression Transformation different from the Function Transformation?
    • Workflows
      • What is a Workflow in Astera?
      • How do I trigger a task if at least one of a set of tasks fails?
      • Can I perform an action based on whether a file has data?
    • Scheduler
      • How can I schedule a job to run every x hours?
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  • Video
  • Use Case
  • How to Work with Database Lookup in Astera

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  1. DATAFLOWS
  2. Transformations

Database Lookup

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Last updated 1 year ago

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The Database Lookup object in Astera is used to look up values from a source. It uses a database table that contains the lookup values as well as a set of corresponding output values. When the lookup is performed, the object returns either a single output field or multiple output fields, depending on the nature of the lookup table. Similarly, the lookup can be performed based on one lookup field or multiple lookup fields. In each case, the output field or fields are returned from the records in which the lookup values match the incoming values.

Video

Use Case

In this use case, we have a sample Customers dataset that is stored in a database table. Within this dataset, there is a field that contains the country of residence for each customer. We have another database table that contains all of these countries and their corresponding codes. Our goal is to replace the full country names with codes while writing the customer dataset to an Excel file. To do this, we will use a Database Lookup object.

How to Work with Database Lookup in Astera

  1. Drag the relevant source object from the Toolbox and drop it onto the designer. In this case, we will select the Database Table Source object from Toolbox > Sources > Database Table Source and configure it so that it reads data from the Customers dataset.

To preview the data, right-click on the object header and select Preview Output from the context menu. Here, you can see that there is a field that contains each customers’ country of residence.

  1. Drag the Database Lookup object from Toolbox > Transformations > Database Lookup and drop it onto the designer.

  1. Right-click on the header of the Database Lookup object and select Properties from the context menu.

This will open a new window on your screen.

Here, you are required to configure the properties for the Database Lookup object.

  1. On the Database Connection window, enter the details for the database you wish to connect to.

  • Use the Data Provider drop-down list to specify which database provider you wish to connect to. The required credentials will vary according to your chosen provider.

  • Provide the required credentials. Alternatively, use the Recently Used drop-down list to connect to a recently connected database.

  • Test Connection to ensure that you have successfully connected to the database. A new window will open, showing whether your test is successful or has ended in an error. When the connection has been successfully established, close it by clicking OK, and then click Next.

  1. The next window is the Database Lookup Map Properties window. Here, you can pick a table from the database that you have connected to.

In this case, we will select the table named CountryCodeLookup. This table contains the code for each country and will serve as the lookup table in our use case.

In the text box provided under the Pick Table option, you can enter a where clause to modify the lookup query. In this case, we will leave it empty.

Once you have chosen a table, click Next.

  1. On the next window, you can choose a Lookup Cache Type from the following options:

No Caching: No data will be stored in a cache. This option is selected by default.

Static: The lookup values are stored in a cache. Once the cache is created, the transformation object will always query the cache instead of the lookup table. When you select this option, the following sub-options are enabled:

  • Fill Cache With All Lookup Values at Start: Fills the cache with all of the lookup values at the start and continues to use this cache for every lookup.

  • Cache After First Use: Uses the database table for the first lookup and fills the cache right after it is done. This cache is then used for every subsequent lookup. Checking this option enables another sub-option:

    • Cache Commit Count: Defines the number of records collected per cache chunk before they are committed to the cache.

Dynamic: The lookup values are stored in a temporary cache file, which is deleted once the dataflow has been executed. When you select this option, the following sub-options are enabled:

  • Fill Cache With All Lookup Values at Start: Fills the cache with all of the lookup values at the start and continues to use this cache for every lookup.

  • Cache After First Use: Uses the database table for the first lookup and fills the cache right after it is done. This cache is then used for every subsequent lookup. Checking this option enables other sub-options:

    • Cache Commit Count: Defines the number of records collected per cache chunk before they are committed to the cache.

    • Cache Key Column: Defines a matching key field to check whether a record already exists in the cache.

Persistent: Saves the lookup values in a cache file that can be reused for future lookups. When you choose this option, the following sub-options are enabled:

  • Rebuild Persistent Cache on Next Run: Checking this option will allow the contents of the cache file to be modified after every run.

  • Cache File Name: Here, you can enter a name for your cache file.

In this case, we will select the No Caching option. Once you are done, click Next.

  1. On the Lookup Options window, you can choose between multiple lookup options.

This page provides a set of options for different scenarios that could be faced during a lookup.

If Multiple Values Are Found

Multiple Matches Found Option**:** This option provides the flexibility to choose the output value if more than one matches are found for a single value in the lookup table. You can select one out of the three options that appear in the drop-down list:

  • Return First: Returns the first matched value.

  • Return Last: Returns the last value among all matched values.

  • Return All: Returns all matched values.

If Value Is Not Found In the Lookup List

If no lookup values are found for a source value, you can choose from the following options to be appended with the output:

  • No Message: The output value will be the same as the input value and no message will appear with it.

  • Add Error: An error message will appear with the output.

  • Add Warning: A warning message will appear with the output.

If Value Is Not Found in the Lookup List, Assign Value

If no lookup value is found for a source value, you can assign an output value of your choice.

  • Assign Source Value: Returns the source value in the output.

  • Assign Null: Returns null in the output.

  • This Value: Allows you to enter any value that will be returned in the output.

In this case, there is only one code for each country. Therefore, we will choose Return First from the drop-down list in the Multiple Matches Found Option. Moreover, we will leave the other options at their default selection i.e. No Message under If Value Is Not Found in the Lookup List, and Assign Null under If Value Is Not Found, Assign Value.

Once you are done choosing the options, click Next.

  1. On the Config Parameters window, you can define certain parameters for the Database Lookup object.

These parameters facilitate an easier deployment of flows by excluding hardcoded values and providing a more convenient method of configuration. If left blank, they will assume the default values that were initially assigned to them.

In this case, we will leave them blank. Click Next.

  1. On the last window, which is the General Options window, you will be provided with a text box to add Comments. The General Options in this window have been disabled.

You are now done configuring the Database Lookup object. Click OK to close the configuration window.

  1. Expand the Database Lookup object to view the layout of the lookup table. In this case, it contains two fields, Country and Code. The former contains the full name of each country and the latter contains each country’s code.

  1. Map the Country field from the Database Table Source object to its counterpart in the Database Lookup object.

  1. Drag an Excel Workbook Destination object from Toolbox > Destinations > Excel Workbook Destination and drop it onto the designer. Configure the object by providing a name and the path to the directory and folder where you want to save your destination file.

  1. Auto-map the source dataset to the destination object.

  1. Delete the mapping link between the Country fields in the source and destination. To do this, right-click on the mapping link and select Delete from the context menu.

  1. Map the Code field from the Database Lookup object to the Country field in the destination object. This is what the final dataflow should look like:

  1. Right-click on the destination object’s header and select Preview Output from the context menu.

In the Data Preview window, you will see that each county name has been replaced by its corresponding code.

This concludes using the Database Lookup Transformation object in Astera.

To learn how you can configure a Database Table Source object, click .

To learn how you can configure an Excel Workbook Destination object, click .

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