Teradata Execute

In this article

Snap type

Write


Description

This Snap allows you to execute a Teradata statement/query.

You can drop your database with it, so be cautious.

Valid JSON paths that are defined in the where clause for queries/statements will be substituted with values from an incoming document. Documents will be written to the error view if the document is missing a value to be substituted into the query/statement. 

If a select query is executed, the query's results are merged into the incoming document and any existing keys will have their values overwritten. On the other hand, the original document is written if there are no results from the query.


The Teradata Execute Snap is for simple DML (SELECT, INSERT, UPDATE, DELETE) type statements. 

Prerequisites

None


Support and limitationsWorks in Ultra Task Pipelines.
Behavior Change

No macro found named "Behavior change in Database Execute Snaps" on page "//docs-snaplogic.atlassian.net/wiki/spaces/SD/pages/31424514/Azure+SQL+-+Execute" in space "https".

If you're experiencing issues please see our Troubleshooting Guide.

Account

This Snap uses account references created on the Accounts page of SnapLogic Manager to handle access to this endpoint. See Configuring Teradata Database Accounts for information on setting up this type of account.

Views
InputThis Snap has at most one document input view. If the input view is defined, then the where clause can substitute incoming values for a given expression.
OutputThis Snap has at most one document output view. If an output view is available and an update/insert/merge/delete statement was executed, then the original document that was used to create the statement will be output with the status of the statement executed.
Error

This Snap has at most one document error view and produces zero or more documents in the view.

Database write Snaps output all records of a batch (as configured in your account settings) to the error view if the write fails during batch processing.

Settings

Label*


Specify the name for the Snap. You can modify this to be more specific, especially if you have more than one of the same Snap in your Pipeline.

Default ValueTeradata Execute
ExampleTeradata Execute

SQL statement*


Specify the SQL statement to execute on the server. 

There are two possible scenarios that you encounter when working with SQL statements in SnapLogic. You must understand the following scenarios to successfully execute your SQL statements: 

Scenarios to successfully execute your SQL statements

Scenario 1: Executing SQL statements without expressions

If the expression toggle of the SQL statement field is disabled:

  • The SQL statement must not be within quotes. 
  • The $<variable_name> parts of the SQL statement are expressions. In the below example, $id and $book.

For example:

Additionally, the JSON path is allowed only in the WHERE clause. If the SQL statement starts with SELECT (case-insensitive), the Snap regards it as a select-type query and executes once per input document. If not, it regards it as write-type query and executes in batch mode.

Scenario 2: Executing SQL queries with expressions 

If the expression toggle of the SQL statement field is selected: 

  • The SQL statement must be within quotes. 
  • The + $<variable_name> + parts of the SQL statement are expressions, and must not be within quotes. In the below example, $tablename.
  • The $<variable_name> parts of the SQL statement are bind parameter, and must be within quotes. In the below example, $id and $book.


Table name and column names must not be provided as bind parameters. Only values can be provided as bind parameters.


For example:


 
Known issue: When the SQL statement property is an expression, the Pipeline parameters are shown in the suggest, but not the input schema.

  • The non-expression form uses bind parameters, so it is much faster than executing N arbitrary SQL expressions.
    With the SQL statement property set as an expression, the Snap can be exposed to SQL injection. Please use this feature with caution.
  • The '$' sign and identifier characters, such as double quotes (“), single quotes ('), or back quotes (`), are reserved characters and should not be used in comments or for purposes other than their originally intended purpose.

Single quotes in values must be escaped

Any relational database (RDBMS) treats single quotes (') as special symbols. So, single quotes in the data or values passed through a DML query may cause the Snap to fail when the query is executed. Ensure that you pass two consecutive single quotes in place of one within these values to escape the single quote through these queries.

For example:

If String To pass this valueUse
Has no single quotes
Schaum Series
'Schaum Series'
Contains single quotes
O'Reilly's Publication
'O''Reilly''s Publication'

Default Value: [None]

Pass through


Select this checkbox to pass the input document to the output view under the key 'original'. This property applies only to the Execute Snaps with SELECT statement.

Default Value: Selected 

Ignore empty result


Select this checkbox to ignore empty result; no document will be written to the output view when a SELECT operation does not produce any result.
If you deselect this checkbox and select the Pass through checkbox, the input document will be passed to the output view.

Default Value: Not selected 

Number of retries

Specify the maximum number of reconnection attempts that the Snap must perform, in case of connection failure or timeout.

Default Value: 0

Retry interval (seconds)


Enter in seconds the duration for which the Snap must wait between two reconnection attempts, until the number of retries is reached.

Default Value: 1

Auto commit

Select one of the options for this property to override the state of the Auto commit property on the account. The Auto commit at the Snap-level has three values: TrueFalse, and Use account setting. The expected functionality for these modes are:

  •  True - The Snap will execute with auto-commit enabled regardless of the value set for Auto commit in the Account used by the Snap.
  •  False - The Snap will execute with auto-commit disabled regardless of the value set for Auto commit in the Account used by the Snap.
  • Use account setting - The Snap will execute with Auto commit property value inherited by the Account used by the Snap.

Default Value: Use account setting
ExampleFalse

'Auto commit' may be enabled for certain use cases if PostgreSQL jdbc driver is used in either Redshift, PostgreSQL or generic JDBC Snap. But the JDBC driver may cause out of memory issues when Select statements are executed. In those cases, “Auto commit" in Snap property should be set to ‘False’ and the Fetch size in the “Account setting" can be increased for optimal performance.

Behavior of DML Queries in Database Execute Snap when auto-commit is false

DDL queries used in the Database Execute Snap will be committed by the Database itself, regardless of the Auto-commit setting.
When Auto commit is set to false for the DML queries, the commit is called at the end of the Snap's execution.
The Auto commit needs to be true in a scenario where the downstream Snap does depend on the data processed on an Upstream Database Execute Snap containing a DML query.
When the Auto commit is set to the Use account setting on the Snap, the account level commit needs to be enabled.

Advanced options

Select the option ‘Timestamp with microsecond precision’ to support the microsecond precision for TIMESTAMP data type. The SELECT query for TIMESTAMP columns produces string values with microsecond precision in the output documents.

Default Value: None

Snap Execution

Select 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.

  

Example


In this example, we shall execute various commands using the Teradata Execute Snap. This pipeline creates a table, inserts the data into the table and reads the data using the respective execute commands (CREATE, INSERT and SELECT).

 

1. Create a table, Snaplogic.character_datatype  under the schema name Snaplogic. The table has 4 columns: INTEGER, CHAR, VARCHAR and CLOB .

2. Insert the required data into the table Snaplogic.character_datatype using the Teradata Execute Snap.

3. We use the Teradata Execute Snap again and select the data from the table Snaplogic.character_datatype1 using the SELECT command.

Successful execution of the Pipeline displays the following preview:

Snap Pack History

 Click to view/expand
Release Snap Pack VersionDateType  Updates
August 2022main17386 StableUpgraded with the latest SnapLogic Platform release.
4.29 Patch429patches16235 Latest

Fixed an issue with Teradata Execute Snap where the Snap did not display valid error message when the delete condition is invalid.

4.29main15993 Stable

Enhanced the Teradata FastExport Snap with Character Set dropdown list to support encoding of data when you export data from the Teradata Database.

4.28main14627 StableUpgraded with the latest SnapLogic Platform release.
4.27main12833 Stable

Enhanced the Teradata Execute Snap to invoke stored procedures.

4.26main11181 StableUpgraded with the latest SnapLogic Platform release.
4.25 Patch425patches11008 Latest

Improved the error messages for all the Snaps in the Teradata Snap Pack where the Snaps fail with a null pointer exception error when the account reference provided is invalid. 

4.25main9554
 
StableUpgraded with the latest SnapLogic Platform release.

4.24 Patch

424patches8799 Latest
  • Enhanced the Teradata Execute Snap by adding a new field, Advanced options, which extends support with microsecond precision for TIMESTAMP data type.
  • Fixed an issue in the TPT Load Snap where the Snap failed to load data into the table while creating an output.
  • Fixed an issue with the TPT Load Snap wherein now a null value is loaded as null and empty string is loaded as empty string.

    • This fix may cause existing pipelines to fail if empty string values are expected to be loaded as null.

    • Following are the new configurations:

      • VARCHAR QuotedData= Optional

      • VARCHAR OpenQuoteMark= \”

      • VARCHAR NullColumns= Yes

4.24main8556
Stable

Enhanced the Teradata Select Snap to return only the selected output fields or columns in the output schema (second output view) using the Fetch Output Fields In Schema check box. If the Output Fields field is empty all the columns are visible.

4.23main7430
 
Stable

Fixes the multi-line value issue and issue in the TPT Load Snap where the Snap writes null for both an empty string and null values in the input data. The fix for this issue was to add the following three lines in the script and wrap all the values in double quotes unless they are null while writing the input data into a temp CSV file. 
VARCHAR QuotedData = 'Optional',
VARCHAR OpenQuoteMark = '\"'
VARCHAR NullColumns = 'Yes'

This fix may cause existing pipelines to fail if empty string values are expected to be loaded as null.



4.22main6403
 
StableUpgraded with the latest SnapLogic Platform release.

4.21 Patch

421patches6272 Latest

Fixed the issue where Snowflake SCD2 Snap generates two output documents despite no changes to Cause-historization fields with DATE, TIME and TIMESTAMP Snowflake data types, and with Ignore unchanged rows field selected.

4.21 Patch

421patches6144 Latest

Fixed the following issues with DB Snaps:

  • The connection thread waits indefinitely causing the subsequent connection requests to become unresponsive.
  • Connection leaks occur during Pipeline execution.

4.21 Patch

MULTIPLE8841 Latest

Fixed the connection issue in Database Snaps by detecting and closing open connections after the Snap execution ends. 

4.21snapsmrc542

 

StableUpgraded with the latest SnapLogic Platform release.
4.20snapsmrc535
 
StableUpgraded with the latest SnapLogic Platform release.

4.19 Patch 

db/teradata8414 LatestFixed an issue with the TPT Update Snap wherein the Snap is unable to perform operations when:
  • An expression is used in the Update condition property.
  • Input data contain the character '?'.
4.19snaprsmrc528
 
StableUpgraded with the latest SnapLogic Platform release.
4.18snapsmrc523
 
StableUpgraded with the latest SnapLogic Platform release.
4.17ALL7402
 
Latest

Pushed automatic rebuild of the latest version of each Snap Pack to SnapLogic UAT and Elastic servers.

4.17snapsmrc515
 
Latest
  • Fixed an issue with the Teradata Execute Snap wherein the Snap would send the input document to the output view even if the Pass through field is not selected in the Snap configuration. With this fix, the Snap sends the input document to the output view, under the key original, only if you select the Pass through field.
  • Added the Snap Execution field to all Standard-mode Snaps. In some Snaps, this field replaces the existing Execute during preview check box.
4.16snapsmrc508
 
StableUpgraded with the latest SnapLogic Platform release.

4.15 Patch 

db/teradata6338 Latest

Replaced Max idle time and Idle connection test period properties with Max life time and Idle Timeout properties respectively, in the Account configuration. The new properties fix the connection release issues that were occurring due to default/restricted DB Account settings.

4.15snapsmrc500
 
StableUpgraded with the latest SnapLogic Platform release.
4.14snapsmrc490
 
StableUpgraded with the latest SnapLogic Platform release.
4.13

snapsmrc486

 
StableUpgraded with the latest SnapLogic Platform release.
4.12

snapsmrc480

 
StableUpgraded with the latest SnapLogic Platform release.
4.11snapsmrc465
 
StableUpgraded with the latest SnapLogic Platform release.
4.10

snapsmrc414

 
Stable

Added Auto commit property to the Select and Execute Snaps at the Snap level to support overriding of the Auto commit property at the Account level.

4.9.0 Patch

teradata3077 Latest

Fixed an issue regarding connection not closed after login failure; Expose autocommit for "Select into" statement in PostgreSQL Execute Snap and Redshift Execute Snap

4.9snapsmrc405
 
Stable
  • Enhanced the Output view of the Snap with Order Summary field that displays the output values (added to the out, err, status, classpath and env fields of the single output view that display the subprocess only).
  • Teradata Export to HDFS Snap supported with Dynamic account.
4.8

snapsmrc398

 
Stable
  • Introduced the TPT Delete, Insert, Load, Upsert and Update Snaps in this release.
  • Introduced Teradata Export to HDFS Snap in this release.
  • Info tab added to accounts.
  • Database accounts now invalidate connection pools if account properties are modified and login attempts fail.
4.7

snapsmrc382

 
Stable
  • Introduced the Teradata FastLoad and Execute Snaps in this release.
  • Migration impact: In Teradata FastExport, the values of the Data Format field have been standardized to be in all caps. Existing pipelines that use the values of Binary, Text, or Unformatted will fail unless the new value of BINARY, TEXT, or UNFORMAT are used.
4.6snapsmrc362
 
Stable

Snap Pack introduced in 4.6.0. This includes only Teradata extract functionality to move data out of Teradata database using the FastExport Utility. It does not include Snaps for load, select, insert, delete, execute or others at this time. It also does not utilize the Teradata Parallel Transporter to extract data.