Create and Use Parameters in Flows

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</noscript><div id="app" class="wrapper"><header id="tableau-help-article-header" class="container--full-width quick-help-header"><div class="container--centered"><div class="header__back-button"><back-button title="Go back"/></div><div class="header__mobile-menu quick-help-hidden"><menu-tree-toggle/></div><div class="header__logo quick-help-hidden"><a href="https://www.tableau.com/en-us/"><img src="./Resources/tableau-logo.png" class="header__logo__img" alt="Tableau"/></a></div><div class="header__search"><search-header-help placeholder="Search"/></div><div class="header__home-button"><home-button title="Go home"/></div></div></header><div class="container--navigation-top quick-help-hidden content-only-hidden"><div id="help-subheader" class="subheader print-hidden"><div class="container--centered"><h4 class="heading--subheader">Tableau Prep Help</h4></div></div><div class="container--top-links"><div class="container--centered container--breadcrumbs"><div><breadcrumb-links-help/></div></div><div id="help-container-menu-headings" class="container--menu-headings"><nav class="nav-medium-screen"><menu-heading-links-static-help menu-title="In this article" :disabled="false" :headings="pageHeadings"/></nav></div></div></div><div class="section--main container--full-width"><div class="container--centered"><nav class="nav-side nav-side--left" role="navigation"><menu-tree-help menu-title="Contents"/></nav><article role="main"><h1 id="contentH1">Create and Use Parameters in Flows</h1><div class="caption article__tags content-only-hidden quick-help-hidden"><span class="article__tags--applies-to">Applies to: Tableau Prep</span><br/><span class="article__tags--role"> </span></div><div id="content-body">&#13; <p><i>Supported in Tableau Prep Builder version 2021.4.1 and later and on the web in Tableau Cloud and Tableau Server version 2021.4.0 and later</i>&#13; <p class="note"><b>Note</b>: The content in this topic applies to authoring flows in Tableau Prep Builder and on the web, unless specifically noted. For more information about authoring flows on the web, see Tableau Prep on the Web in the <a href="https://help.tableau.com/current/server/en-us/prep_web_auth.htm" target="_blank">Tableau Server<span class="sr-only">(Link opens in a new window)</span></a> and <a href="https://help.tableau.com/current/online/en-us/prep_web_auth.htm" target="_blank">Tableau Cloud<span class="sr-only">(Link opens in a new window)</span></a> help.</p>&#13; <p> If you often reuse flows using different data with the same schema, you can create and apply parameters to your flows to easily transition between scenarios. A parameter is a global placeholder value such as a number, text value, or boolean value that can replace a constant value in a flow.</p>&#13; <p>Instead of building and maintaining multiple flows, you can now build one flow and use parameters to run the flow with your different data sets. For example, you can create a parameter for various sales regions, then apply a parameter value to the input file path to run the flow using just that region's data. </p>&#13; <h2 is="heading-item" :level="2" id="where-can-i-apply--parameters"><a name="where_parameters_used"/>Where can I apply parameters?</h2>&#13; <p>Parameters can be applied to file names, paths, table names, filter expressions, and calculated fields, depending on the step type. Starting in version 2022.1.1, you can even include parameter override values when running flows using the REST API. For more information, see <a href="https://help.tableau.com/current/api/rest_api/en-us/REST/rest_api_ref_flow.htm" target="_blank">Flow Methods<span class="sr-only">(Link opens in a new window)</span></a> in the Tableau Rest API help.</p>&#13; <p> The following table lists the locations where you can apply parameters for each step type.</p>&#13; <li value="1">Connect to file: Use parameters in the file name or file path</li>&#13; <li value="2">Connect to database: Use parameters for the table name and in Custom SQL</li>&#13; <li value="3">Expression editor: Filters </li>&#13; <li value="1">Output to file: Use parameters in the file name or file path and starting in version 2022.1.1, the Microsoft Excel worksheet name.</li>&#13; <li value="2">Output to server: Use parameters in the published data source name</li>&#13; <li value="3">Output to database: Use parameters for the table name and starting in version 2022.1.1, in SQL scripts that you run before or after writing the flow output to a database.</li>&#13; <h2 is="heading-item" :level="2" id="create-parameters"><a name="create_parameters"/>Create parameters</h2>&#13; <p>Parameters are specific to the flow where they are used. Create parameters from the top menu, then define the values that apply to them. You can also define parameters that accept all values, which means any flow user can enter any value when running the flow.</p>&#13; <p>You can make flow parameter values required or optional. When running the flow, users are prompted to enter the parameter values. Required parameter values must be entered before the user can run the flow. Optional parameter values can be entered or you can accept the current (default) value. The parameter values are then applied to the flow run everywhere that parameter is used.</p>&#13; <p class="note"><b>Note</b>: To run or schedule flows that include parameters on <span class="VariablesTabsProductServer">Tableau Server</span> or <span class="VariablesTabsProductOnline">Tableau Cloud</span>, your administrator must enable the <span class="uicontrol">Flow Parameter</span> settings on your server. For more information, see <b>Create and Interact with Flows on the Web</b> in the <a href="https://help.tableau.com/current/server/en-us/web_author_flows.htm#flow-parameters" target="_blank">Tableau Server<span class="sr-only">(Link opens in a new window)</span></a> or <a href="https://help.tableau.com/current/online/en-us/web_author_flows.htm#flow-parameters" target="_blank">Tableau Cloud<span class="sr-only">(Link opens in a new window)</span></a> help.</p>&#13; <p>From the top menu, click the <span class="uicontrol">Parameter</span> <img src="Img/prep_parameter_icon.png" alt=""/> icon, then click <span class="uicontrol">Create Parameter</span>.</p>&#13; <p>In the <span class="uicontrol">Create Parameter</span> dialog, enter a name and a description (optional). The parameter name must be unique. This is the value that shows in the user interface when you add a parameter.</p>&#13; <p>If you include a description, users can see this information on hover (starting in version 2022.1.1) in the parameters list and where parameters are used.</p>&#13; <p>Select one of the following data types. Parameter values must match the data type that you select.</p>&#13; <li value="1">Number (whole or decimal)</li>&#13; <li value="2">String</li>&#13; <li value="3">Boolean</li>&#13; <p>Specify the <span class="uicontrol">Allowable values</span>. These are the values that users can enter in the parameter.</p>&#13; <p><span class="uicontrol">All</span>: This option lets users type in any value for the parameter, even when running the flow.</p>&#13; <p class="note"><b>Note</b>: Using this option for parameters that can be used in input and output steps can be a security risk. For example, Custom SQL queries that allow any value to be entered can expose your data assets to SQL injection attacks.</p>&#13; <li value="2"><span class="uicontrol">List</span>: Enter a list of values that users can choose from when applying the parameter. To enter multiple values, press <b>Enter</b> after each entry.</li>&#13; <li value="5">(optional) Select <span class="uicontrol">Require selection at run time</span> (<span class="uicontrol">Prompt for value at run time</span> in prior releases). This makes the parameter required. The user is required to enter a value when running or scheduling the flow. </li>&#13; <p>Enter a <span class="uicontrol">Current value</span>. This is a required value and acts as a default value for the parameter. </p>&#13; <li value="1"><span class="uicontrol">All</span>: Enter a value.</li>&#13; <li value="2"><span class="uicontrol">List</span>: Tableau uses the first value in your list. Use the drop-down option to change it.</li>&#13; <li value="3"><span class="uicontrol">Boolean</span>: Select <span class="uicontrol">True</span> or <span class="uicontrol">False</span>.</li>&#13; <li value="7">Click <span class="uicontrol">OK</span> to save the parameter.</li>&#13; <h3 is="heading-item" :level="3" id="change-the-parameter-default-value">Change the parameter default value</h3>&#13; <p>When you create a parameter, you have to specify a current (default) value. If a parameter is included in a flow, this value is used to:</p>&#13; <li value="1"> Run Custom SQL queries defined in an input step.</li>&#13; <li value="2">Fill in optional parameters that aren't specified at run time.</li>&#13; <li value="3">Replace the parameter as a static value in saved steps (version 2022.1.1 and later). </li>&#13; <li value="4">Replace the parameter as a static value in file paths when publishing flows with packaged data sets. </li>&#13; <p>You can change the value at any time. From the top menu you can edit the parameter or use the <span class="uicontrol">Set</span> button on the parameter list. From within the flow, you can use the <span class="uicontrol">Set</span> button anywhere the parameter is applied. When you do this, it resets the parameter's current (default) value everywhere that parameter is used, even in Custom SQL queries.</p>&#13; <h4>Edit parameters</h4>&#13; <li value="1">From the top menu, click the <span class="uicontrol">Parameter</span><img src="Img/prep_parameter_icon.png" alt=""/> icon.</li>&#13; <li value="2">Click <span class="uicontrol">Edit parameter</span>.</li>&#13; <p>In the <span class="uicontrol">Edit Parameter</span> dialog, make any changes, then click <span class="uicontrol">OK</span>.</p>&#13; <h4>Reset parameter default values with the Set button</h4>&#13; <p>To quickly reset the parameter default value, use the <span class="uicontrol">Set</span> button. The button shows you a count indicating the number of places in the flow where the parameter is used.</p>&#13; <p>To highlight the steps in the flow that use the parameter, click <span class="uicontrol">View in flow</span> on the parameter dialog. If there is only one place the parameter is used, you are taken directly to that step with the profile pane opened.</p>&#13; <li value="1">Do one of the following:<ul><li value="1"><p>From the top menu, click the <span class="uicontrol">Parameter</span><img src="Img/prep_parameter_icon.png" alt=""/> icon. Use this option to reset parameter values used anywhere in the flow, or when used in filters and calculated fields.</p><p><img src="Img/prep_parameters_edit3.jpg" alt=""/></p></li><li value="2"><p>Click on the parameter where it is applied in the flow. You can use this option for parameters used in file names, file paths, table names, custom SQL, and pre and post SQL scripts.</p><p><img src="Img/prep_parameters_set2.png" alt=""/></p></li></ul></li>&#13; <li value="2">Select or enter the parameter value.</li>&#13; <p>Click <span class="uicontrol">Set</span> to apply the change.</p>&#13; <h2 is="heading-item" :level="2" id="apply-parameters-to-your-flow"><a name="apply_parameters"/>Apply parameters to your flow</h2>&#13; <p>After you create your parameters, you can apply them to various places throughout your flow, depending on the step type. When the flow is run, the parameter values are applied to that flow run to produce the output for the specific data scenario.</p>&#13; <h3 is="heading-item" :level="3" id="apply-parameters-to-input-steps"><a name="parameters_input_steps"/>Apply parameters to input steps</h3>&#13; <p>In an Input step you can use parameters to replace a file name, sections of your file path, a database table name, or when using Custom SQL.</p>&#13; <h4>File name or file path</h4>&#13; <p><i>This option is not available when editing or authoring flows on the web. </i>&#13; <p>You can include parameters in your file path with some exceptions. Starting in version 2022.1.1, you can also see a preview of the parameter values.</p>&#13; <p><b>Exceptions</b>&#13; <li value="1"> Starting in version 2022.1.1, you can schedule and run flows on the web that include parameters in the input file path. If using an earlier version, run flows in Tableau Prep Builder or from the command line.</li>&#13; <p>To include parameters in the file path when publishing flows to the web, a direct file connection is required. Otherwise, the parameter is converted to a static value using the <span class="uicontrol">Current value</span>.</p>&#13; <p class="note"><b>Note</b>: Direct file connections require that the file locations are included in your organization's safe list. For more information see <a href="https://help.tableau.com/current/server/en-us/prep_conductor_configure_network_shares.htm" target="_blank">Safe List Input and Output Locations<span class="sr-only">(Link opens in a new window)</span></a> in the Tableau Server help.</p>&#13; <p><b>Apply a parameter to a file name or path</b>&#13; <li value="1">In the <span class="uicontrol">Settings</span> tab, in the file path, place your cursor in the location where you want to add the parameter.</li>&#13; <p>Click the parameter <img src="Img/prep_parameter_icon.png" alt=""/> icon and select your parameter.</p>&#13; <h4>Database table</h4>&#13; <p>When using parameters in table names, the entire table name must be the parameter. Using parameters for parts of a table name is not currently supported.</p>&#13; <p class="note"><b>Note</b>: Using a parameter for a table name in a Google BigQuery input connection is not yet supported.</p>&#13; <li value="1">In the <span class="uicontrol">Settings</span> tab, in the <span class="uicontrol">Table</span> field, click the drop-down menu.</li>&#13; <p>Select <span class="uicontrol">Use Parameter</span>, then select the parameter from the list.</p>&#13; <li value="1">In the <span class="uicontrol">Connections</span> pane, click <span class="uicontrol">Custom SQL</span>.</li>&#13; <p>In the <span class="uicontrol">Custom SQL</span> tab, type or paste the query into the text box.</p>&#13; <p>Click the parameter <img src="Img/prep_parameter_icon.png" alt=""/> icon and select your parameter.</p>&#13; <p>Click <span class="uicontrol">Run</span> to run your query. You won't be prompted to enter a parameter value until you run the flow. Instead the query will run initially using the parameter's <span class="uicontrol">Current value</span>. </p>&#13; <p class="note"><b>Note</b>: If the parameter is used elsewhere in the flow and the <span class="uicontrol">Current Value</span> is reset, that change can impact your query.</p>&#13; <h3 is="heading-item" :level="3" id="apply-parameters-to-output-steps"><a name="output_parameters"/>Apply parameters to output steps</h3>&#13; <p>In an Output step you can use parameters in the following places:</p>&#13; <li value="1">File name</li>&#13; <li value="2">Sections of your file path</li>&#13; <li value="3">Published data source name</li>&#13; <li value="4"> Database table name</li>&#13; <li value="5">Microsoft Excel worksheet name (version 2022.1.1 and later)</li>&#13; <li value="6">Custom SQL scripts that run before or after writing flow output data to a database (version 2022.1.1 and later)</li>&#13; <h4>File name or file path</h4>&#13; <p><i>This output option is not available when creating or editing flows on the web </i>&#13; <li value="1">In the <span class="uicontrol">Output</span> pane, select <span class="uicontrol">File</span> from the <span class="uicontrol">Save output to</span> drop-down list.</li>&#13; <p>In the <span class="uicontrol">Name</span> or <span class="uicontrol">Location</span> field, click the parameter <img src="Img/prep_parameter_icon.png" alt=""/> icon and select your parameter.</p>&#13; <p>For file path, place your cursor in the location where you want to add the parameter.</p>&#13; <p>When you run the flow you'll be prompted to enter your parameter values.</p>&#13; <h4>Published data source name </h4>&#13; <li value="1">In the <span class="uicontrol">Output</span> pane, in the <span class="uicontrol">Save output to</span> drop-down list, select <span class="uicontrol">Published data source</span>.</li>&#13; <p>In the <span class="uicontrol">Name</span> field, click the parameter <img src="Img/prep_parameter_icon.png" alt=""/> icon and select your parameter.</p>&#13; <p>When you run the flow you'll be prompted to enter your parameter values.</p>&#13; <h4>Database table and Before and After Custom SQL</h4>&#13; <li value="1">In the <span class="uicontrol">Output</span> tab, in the <span class="uicontrol">Save output to</span> drop-down list, select <span class="uicontrol">Database table</span>.</li>&#13; <p>In the <span class="uicontrol">Table</span> field, select <span class="uicontrol">Use Parameter</span>, then select the parameter from the list.</p>&#13; <p>(Optional) Click on the <span class="uicontrol">Custom SQL</span> tab. Starting in version 2022.1.1, you can enter a SQL script with parameters to run <span class="uicontrol">Before</span> and <span class="uicontrol">After</span> the data is written to the table. To include a parameter, click <span class="uicontrol">Insert Parameter</span>, and select your parameter.</p>&#13; <p>For more information about using SQL scripts when writing output to a database, see <a href="prep_save_share.htm#write_to_DB" class="MCXref xref">Save flow output data to external databases</a>.</p>&#13; <p class="note"><b>Note</b>: Parameters used in SQL scripts must be manually deleted. See <a href="#delete_earlier_version" class="MCXref xref">Manually delete parameters</a> for more information.</p>&#13; <p>When you run the flow you'll be prompted to enter your parameter values.</p>&#13; <h3 is="heading-item" :level="3" id="apply-parameters-to-filter-calculations"><a name="filter_parameters"/>Apply parameters to filter calculations</h3>&#13; <p>Use parameters to filter data throughout your flow. Filter your data set in the input step or apply filter parameters at the step or field value level. For example use a filter parameter to only input data for a specific region or filter data in a step to a specific department.</p>&#13; <p class="note"><b>Note</b>: Starting in version 2022.1, you can use copy and paste to reuse filter calculations with parameters in other flows when the same parameter exists with the same name and data type.</p>&#13; <li value="1">From the Input step or toolbar on the profile pane, click <span class="uicontrol">Filter Values</span>. To add a parameter filter to a field, from the <span class="uicontrol">More options</span><img src="Img/prep_moreoptions_icon.png" alt=""/>menu select <span class="uicontrol">Filters</span> &gt; <span class="uicontrol">Calculation</span>.</li>&#13; <p>In the <span class="uicontrol">Add Filter</span> calculation editor, type the name of the parameter to select it from the list (the parameter shows in purple), then click <span class="uicontrol">Save</span> to save your filter.</p>&#13; <p>When you run the flow you'll be prompted to enter your parameter values.</p>&#13; <h3 is="heading-item" :level="3" id="apply-parameters-to-calculated-fields">Apply parameters to calculated fields</h3>&#13; <p>Use parameters to replace constant values in calculations that you use throughout your flow. You can apply calculation parameters at the step or field value level. </p>&#13; <p class="note"><b>Note</b>: Starting in version 2022.1, you can use copy and paste to reuse calculations with parameters in other flows when the same parameter exists with the same name and data type.</p>&#13; <li value="1">From the toolbar on the profile pane, click <span class="uicontrol">Create Calculated Field</span>. To add a parameter to a calculation on a field, from the <span class="uicontrol">More options</span><img src="Img/prep_moreoptions_icon.png" alt=""/>menu select <span class="uicontrol">Create Calculated Field</span> &gt; <span class="uicontrol">Custom Calculation</span>.</li>&#13; <p>In the <span class="uicontrol">Add Field</span> calculation editor, enter your calculation, type the name of the parameter to select it from the list, then click <span class="uicontrol">Save</span> to save your calculation.</p>&#13; <p>When you run the flow you'll be prompted to enter your parameter values.</p>&#13; <h2 is="heading-item" :level="2" id="delete-parameters"><a name="delete_parameters"/>Delete parameters</h2>&#13; <p>To delete parameters that you no longer need, click <span class="uicontrol">Delete Parameter</span> in the <span class="uicontrol">Edit Parameter</span> dialog. This removes any instance of the parameter used throughout the flow and replaces it with the parameter's <span class="uicontrol">Current value</span>. This action can't be undone.</p>&#13; <p class="note"><b>Note</b>: The options to delete parameters in a flow vary depending on your version. Use the instructions below for version 2022.1 and later. Use <a href="#delete_earlier_version" class="MCXref xref">Manually delete parameters</a> for previous versions and to delete parameters used in Custom SQL scripts that run before or after writing output to a database.</p>&#13; <li value="1">From the top menu, click the parameter <img src="Img/prep_parameter_icon.png" alt=""/> icon drop-down menu, then click <span class="uicontrol">Edit parameter</span> for the parameter you want to delete.</li>&#13; <p>In the <span class="uicontrol">Edit Parameter</span> dialog, click <span class="uicontrol">Delete Parameter</span>.</p>&#13; <div is="accordion-item"><span slot="title">Manually delete parameters</span><div slot="content">&#13; <p><i>Applies to version 2021.4.4 and earlier and parameters used in pre and post Custom SQl scripts </i>&#13; <p>Before you can delete a parameter from your parameters list, you must first find and remove all instances of the parameters from your flow, even from the <span class="uicontrol">Changes</span> pane. </p>&#13; <li value="1"> From the top menu, click the parameter <img src="Img/prep_parameter_icon.png" alt=""/> icon drop-down menu.</li>&#13; <p>For the parameter that you want to delete, click <span class="uicontrol">View in flow</span> to find all instances where the parameter is used in the flow.</p>&#13; <p>If the parameter is not used anywhere in the flow skip to step 4.</p>&#13; <li value="3">For each step where the parameter is used, remove the parameter, including deleting any changes listed in the <span class="uicontrol">Changes</span> pane.</li>&#13; <li value="4">From the top menu, click the parameter <img src="Img/prep_parameter_icon.png" alt=""/> icon drop-down menu and for the parameter you want to delete, click <span class="uicontrol">Edit parameter</span>.</li>&#13; <p>In the <span class="uicontrol">Edit Parameter</span> dialog, click <span class="uicontrol">Delete Parameter</span>.</p>&#13; <p>The parameter will be replaced with the parameter's <span class="uicontrol">Current value</span>.</p>&#13; </div><h2 is="heading-item" :level="2" id="run-flows-with-parameters"><a name="run_flows"/>Run flows with parameters</h2>&#13; <p>Running flows that include parameters is the same as running flows that don't have them, except that users are prompted to enter parameter values at run time or when adding the flow to a schedule in <span class="VariablesTabsProductServer">Tableau Server</span> or <span class="VariablesTabsProductOnline">Tableau Cloud</span>.</p>&#13; <p>If a parameter is marked as a required, users must enter a value before they can run the flow. If a parameter is optional, users can enter a value or accept the parameter's <span class="uicontrol">Current value</span> by default.</p>&#13; <p>Required parameters are those that have the <span class="uicontrol">Require selection at run time</span> (<span class="uicontrol">Prompt for value at run time</span> in prior releases) check box selected.</p>&#13; <p>If you run flows using the command line interface and want to override the current (default) parameter values, create a parameters override .json file and include the -p --parameters syntax in your command line. For more information, see <a href="prep_run_commandline.htm" class="MCXref xref">Refresh flow output files from the command line</a>.</p>&#13; <h3 is="heading-item" :level="3" id="run-flows-manually"><a name="run_flow_manual"/>Run flows manually</h3>&#13; <p>When you run a flow from Tableau Prep Builder or manually in <span class="VariablesTabsProductServer">Tableau Server</span> or <span class="VariablesTabsProductOnline">Tableau Cloud</span>, the <span class="uicontrol">Parameters</span> dialog opens when you click <span class="uicontrol">Run</span>.</p>&#13; <li value="1">Enter or select the parameter values. If there are optional parameters in the flow, you can enter the values at this time or accept the current (default) parameter value.</li>&#13; <li value="2">Click <span class="uicontrol">Run Flow</span> to run the flow.</li>&#13; <p>For more information about running flows, see <a href="prep_conductor_publish_flow.htm#run_flows" class="MCXref xref">Publish a Flow to Tableau Server or Tableau Cloud</a>.</p>&#13; <h3 is="heading-item" :level="3" id="run-flows-on-a-schedule"><a name="run_flow_schedule"/>Run flows on a schedule</h3>&#13; <p>When you schedule flows to run on <span class="VariablesTabsProductServer">Tableau Server</span> or <span class="VariablesTabsProductOnline">Tableau Cloud</span>, you will need to enter any required parameter values when scheduling the flows.</p>&#13; <p>On the <span class="uicontrol">New Tasks</span> or <span class="uicontrol">Linked Tasks</span> tab, in the <span class="uicontrol">Set Parameters</span> section, enter or select the parameter values. If there are optional parameters in the flow, you can enter the values at this time or leave the field empty to use the current (default) parameter value.</p>&#13; <p><b>New Tasks</b>&#13;