SQL Server Execute

You can use this Snap to execute arbitrary SQL queries. This Snap works only with single queries.

Note:
  • You can drop your database with the execution, so we recommend you to be cautious.
  • You can execute stored procedures containing IN, OUT, INOUT parameters using this Snap.


Supported Accounts

  • This is a Write-type Snap.

Snap Type

SQL Server - Execute Snap is a Write-type Snap that executes an SQL Server statement/query.

Support for Ultra Pipelines

Works in Ultra Pipelines.

Limitations & Known Issues

  • When the SQL statement property is an expression, the pipeline parameters are shown in the suggest, but not the input schema.

Snap views

Type Description Examples of upstream and downstream Snaps
Input

This Snap allows zero or one input views.

  • Min: 0
  • Max: 1

If the input view is defined, then the where clause can substitute incoming values for a given expression.
Output

This Snap allows zero or one output view and produces documents in the view.

  • Min: 0
  • Max: 1
  • JSON Formatter
Learn more about Error handling.

Snap settings

Note: Learn about the common controls in the Snap settings dialog.
Field/Field set 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.

Default value: SQL Server - Execute
SQL statement

String/Expression

Required. Specify the SQL statement to execute on the server. Learn more about how to execute SQL statements.

Note:
  • We recommend you to add a single query in the SQL Statement field.
  • You cannot use pipeline parameters within your SQL statement. If you need to use parameters, connect a Mapper Snap before the SQL Snap and provide the values.
  • Avoid using non-standard words, such as GO in SQL statements, as GO is not a recognized keyword in SQL Server.
  • Table name and column names must not be provided as bind parameters. Only values can be provided as bind parameters.
  • Valid JSON paths that are defined in the WHERE clause for queries/statements will be substituted with values from an incoming document.
Note:

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 value Use
Has no single quotes Schaum Series 'Schaum Series'
Contains single quotes O'Reilly's Publication 'O''Reilly''s Publication'

Default value: N/A

Example: INSERT into SnapLogic.book (id, book) VALUES ($id,$book)
Query type

Dropdown list/Expression

Select the type of query for your SQL statement (Read or Write).

When Auto is selected, the Snap tries to determine the query type automatically. If the execution result of the query is not as expected, you can change the query type to Read or Write.

Default value: Auto

Example: Read
Pass through

Checkbox

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 status: Selected
Ignore empty result

Checkbox

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

Default status: Deselected
Number of retries

Integer/Expression

Specify the maximum number of retry attempts the Snap must make in case of network failure.

When you set the Number of retries to more than 0, the Snap generates duplicate records when the connection is not established. To prevent duplicate records, we recommend that you follow one of the following:

  • Set the Number of retries to 0 (default value) to prevent duplicate records from being passed downstream while executing a pipeline.
  • Use a Primary key to prevent records from being inserted into the database.
  • Use an Upsert instead of an Insert statement.

Default value: 0

Example: 3
Retry interval (seconds)

Integer/Expression

Specify the time interval between two successive retry requests. A retry happens only when the previous attempt resulted in an exception.

Default value: 1

Example: 10
Auto commit

Dropdown list

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: True, False, 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.
Note: '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.
Note: If you are executing a DDL statement, such as CREATE, DROP, or ALTER, within a stored procedure or script, the Snap must commit the changes to the database immediately using auto-commit. This is required for the changes to persist in the database. Using a Transaction Snap to commit may not have the desired effect for executing DDL statements within stored procedures.

Default value: Use account setting

Example: True

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

Execute SQL statements

Without expressions

If you do not enable the expression toggle of the SQL statement field, then:

  • 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.

Examples:

Note: 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 a write-type query and executes in batch mode.

With expressions

If you enable the expression toggle of the SQL statement field, then:

  • 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.

Examples:

  • "EMPNO=$EMPNO and ENAME=$EMPNAME"
  • "emp='" + $emp + "'"
  • "EMPNO=" + $EMPNO + " and ENAME='" + $EMPNAME+ "'"
Note:
  • The non-expression form uses bind parameters, so it is much faster than executing N arbitrary SQL expressions.
  • Using expressions that join strings together to create SQL queries or conditions has a potential SQL injection risk and hence unsafe. Ensure that you understand all implications and risks involved before using concatenation of strings with '=' Expression enabled.
  • The '$' 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.

Troubleshooting

Error Reason Resolution
Failure: Batch operation failed. Error code: 102 Incorrect syntax near 'GO'. Rewrite the query without 'GO' and run it.