---

name: data-policies description: This skill should be used when the user asks to "data policy", "dictionary", "field validation", "mandatory field", "read only", "data model", "table schema", "column attributes", or any ServiceNow Data Policy and Dictionary development. license: Apache-2.0 compatibility: Designed for Snow-Code and ServiceNow development metadata: author: groeimetai version: "1.0.0" category: servicenow tools:

• snow_discover_table_fields
• snow_query_table
• snow_find_artifact
• snow_execute_script_with_output

---

Data Policies & Dictionary for ServiceNow

Data Policies enforce data integrity rules. Dictionary controls schema and field behavior.

Architecture

CopyDictionary (sys_dictionary)
    ├── Field Definition
    │   ├── Type, Length, Default
    │   └── Dependent Field
    └── Dictionary Overrides (sys_dictionary_override)

Data Policy (sys_data_policy2)
    └── Data Policy Rules (sys_data_policy_rule)
        └── Condition-based field behaviors

Key Tables

Dictionary Management (ES5)

Create Table

Copy// Create custom table (ES5 ONLY!)
var table = new GlideRecord('sys_db_object');
table.initialize();

table.setValue('name', 'u_custom_table');
table.setValue('label', 'Custom Table');
table.setValue('super_class', 'task');  // Extends task
table.setValue('is_extendable', true);
table.setValue('create_access_controls', true);
table.setValue('live_feed_enabled', false);

table.insert();

Create Field

Copy// Create field on table (ES5 ONLY!)
var field = new GlideRecord('sys_dictionary');
field.initialize();

// Table and element
field.setValue('name', 'u_custom_table');
field.setValue('element', 'u_customer_name');

// Field properties
field.setValue('column_label', 'Customer Name');
field.setValue('internal_type', 'string');
field.setValue('max_length', 100);
field.setValue('mandatory', false);
field.setValue('read_only', false);
field.setValue('display', false);
field.setValue('active', true);

// Default value
field.setValue('default_value', '');

// Reference field specific
// field.setValue('reference', 'customer_account');
// field.setValue('reference_qual', 'active=true');

field.insert();

Field Types

Copy// Common field types
var FIELD_TYPES = {
    STRING: 'string',
    INTEGER: 'integer',
    DECIMAL: 'decimal',
    BOOLEAN: 'boolean',
    GLIDE_DATE: 'glide_date',
    GLIDE_DATE_TIME: 'glide_date_time',
    REFERENCE: 'reference',
    CHOICE: 'choice',
    JOURNAL: 'journal',
    JOURNAL_INPUT: 'journal_input',
    HTML: 'html',
    URL: 'url',
    EMAIL: 'email',
    SCRIPT: 'script',
    CONDITIONS: 'conditions'
};

// Create different field types (ES5 ONLY!)
function createField(tableName, fieldDef) {
    var field = new GlideRecord('sys_dictionary');
    field.initialize();
    field.setValue('name', tableName);
    field.setValue('element', fieldDef.name);
    field.setValue('column_label', fieldDef.label);
    field.setValue('internal_type', fieldDef.type);

    if (fieldDef.maxLength) {
        field.setValue('max_length', fieldDef.maxLength);
    }

    if (fieldDef.reference) {
        field.setValue('reference', fieldDef.reference);
    }

    if (fieldDef.choices) {
        field.setValue('choice', 1);  // Has choices
    }

    return field.insert();
}

Create Choices

Copy// Create choice list values (ES5 ONLY!)
function createChoices(tableName, fieldName, choices) {
    for (var i = 0; i < choices.length; i++) {
        var choice = new GlideRecord('sys_choice');
        choice.initialize();
        choice.setValue('name', tableName);
        choice.setValue('element', fieldName);
        choice.setValue('value', choices[i].value);
        choice.setValue('label', choices[i].label);
        choice.setValue('sequence', (i + 1) * 10);
        choice.setValue('inactive', false);
        choice.insert();
    }
}

// Usage
createChoices('incident', 'u_custom_status', [
    { value: 'pending', label: 'Pending Review' },
    { value: 'approved', label: 'Approved' },
    { value: 'rejected', label: 'Rejected' }
]);

Dictionary Overrides (ES5)

Create Override

Copy// Create dictionary override for scoped app (ES5 ONLY!)
var override = new GlideRecord('sys_dictionary_override');
override.initialize();

// Reference the base field
override.setValue('base_table', 'task');
override.setValue('base_element', 'short_description');

// Target table
override.setValue('name', 'u_custom_table');

// Override properties
override.setValue('column_label', 'Request Summary');
override.setValue('mandatory', true);
override.setValue('read_only', false);
override.setValue('max_length', 200);

// Default value override
override.setValue('default_value', '');

override.insert();

Data Policies (ES5)

Create Data Policy

Copy// Create data policy (ES5 ONLY!)
var policy = new GlideRecord('sys_data_policy2');
policy.initialize();

policy.setValue('model_table', 'incident');
policy.setValue('short_description', 'Resolution Fields Required on Resolve');
policy.setValue('active', true);

// Conditions - when policy applies
policy.setValue('conditions', 'state=6');  // Resolved state

// Apply to forms
policy.setValue('apply_to_client', true);
policy.setValue('apply_to_import_sets', true);
policy.setValue('apply_to_soap', true);

// Reverse
policy.setValue('reverse_if_false', true);

var policySysId = policy.insert();

// Add policy rules
addDataPolicyRule(policySysId, 'resolution_code', true, false, false);
addDataPolicyRule(policySysId, 'close_notes', true, false, false);

Add Policy Rules

Copy// Add data policy rule (ES5 ONLY!)
function addDataPolicyRule(policySysId, fieldName, mandatory, readOnly, hidden) {
    var rule = new GlideRecord('sys_data_policy_rule');
    rule.initialize();
    rule.setValue('sys_data_policy', policySysId);
    rule.setValue('field', fieldName);
    rule.setValue('mandatory', mandatory);
    rule.setValue('read_only', readOnly);
    rule.setValue('visible', !hidden);
    return rule.insert();
}

Complex Data Policy

Copy// Data policy with scripted condition (ES5 ONLY!)
var policy = new GlideRecord('sys_data_policy2');
policy.initialize();

policy.setValue('model_table', 'change_request');
policy.setValue('short_description', 'High Risk Change Requirements');
policy.setValue('active', true);

// Use scripted condition for complex logic
policy.setValue('use_as_condition', true);
policy.setValue('script',
    '(function checkCondition(current) {\n' +
    '    // High risk changes require additional fields\n' +
    '    if (current.risk == "high") {\n' +
    '        return true;\n' +
    '    }\n' +
    '    \n' +
    '    // Also apply to changes affecting critical CIs\n' +
    '    if (current.cmdb_ci) {\n' +
    '        var ci = current.cmdb_ci.getRefRecord();\n' +
    '        if (ci.business_criticality == "1 - most critical") {\n' +
    '            return true;\n' +
    '        }\n' +
    '    }\n' +
    '    \n' +
    '    return false;\n' +
    '})(current);'
);

var policySysId = policy.insert();

// Require additional documentation for high risk
addDataPolicyRule(policySysId, 'implementation_plan', true, false, false);
addDataPolicyRule(policySysId, 'backout_plan', true, false, false);
addDataPolicyRule(policySysId, 'test_plan', true, false, false);
addDataPolicyRule(policySysId, 'justification', true, false, false);

Field Validation (ES5)

Dictionary Attribute Validation

Copy// Add validation to dictionary field (ES5 ONLY!)
var field = new GlideRecord('sys_dictionary');
if (field.get('name', 'incident').get('element', 'u_email')) {
    // Add regex validation
    field.setValue('attributes', 'validate=email');
    field.update();
}

// Common validation attributes
var VALIDATION_ATTRIBUTES = {
    EMAIL: 'validate=email',
    PHONE: 'validate=phone_number',
    URL: 'validate=url',
    CUSTOM: 'validate=script'  // Uses script in Calculated Value
};

Script Validation

Copy// Calculated field with validation (ES5 ONLY!)
// Set in Dictionary > Calculated Value

// Check phone format
(function calculate() {
    var phone = current.getValue('u_phone');
    if (!phone) return '';

    // Format validation
    var phonePattern = /^\+?[1-9]\d{1,14}$/;
    if (!phonePattern.test(phone.replace(/[\s\-\(\)]/g, ''))) {
        gs.addErrorMessage('Invalid phone number format');
        return '';
    }

    return phone;
})();

Schema Queries (ES5)

Get Table Fields

Copy// Get all fields for a table (ES5 ONLY!)
function getTableFields(tableName) {
    var fields = [];

    var dict = new GlideRecord('sys_dictionary');
    dict.addQuery('name', tableName);
    dict.addQuery('internal_type', '!=', 'collection');
    dict.addQuery('active', true);
    dict.orderBy('element');
    dict.query();

    while (dict.next()) {
        fields.push({
            name: dict.getValue('element'),
            label: dict.getValue('column_label'),
            type: dict.getValue('internal_type'),
            mandatory: dict.getValue('mandatory') === 'true',
            reference: dict.getValue('reference'),
            maxLength: dict.getValue('max_length')
        });
    }

    return fields;
}

Check Field Exists

Copy// Check if field exists on table (ES5 ONLY!)
function fieldExists(tableName, fieldName) {
    var dict = new GlideRecord('sys_dictionary');
    dict.addQuery('name', tableName);
    dict.addQuery('element', fieldName);
    dict.query();
    return dict.hasNext();
}

MCP Tool Integration

Available Tools

Example Workflow

Copy// 1. Get table fields
await snow_discover_table_fields({
    table_name: 'incident'
});

// 2. Query data policies
await snow_query_table({
    table: 'sys_data_policy2',
    query: 'model_table=incident^active=true',
    fields: 'short_description,conditions,apply_to_client'
});

// 3. Check dictionary overrides
await snow_query_table({
    table: 'sys_dictionary_override',
    query: 'name=u_custom_table',
    fields: 'base_element,column_label,mandatory,read_only'
});

Best Practices

1. Schema Planning - Design before implementation
2. Field Naming - u_ prefix for custom fields
3. Data Types - Use appropriate types
4. Mandatory Fields - Only when truly required
5. Data Policies - Enforce business rules
6. Performance - Avoid complex calculated fields
7. Documentation - Document custom schema
8. ES5 Only - No modern JavaScript syntax