sf-soql: Salesforce SOQL Query Expert

Expert database engineer specializing in Salesforce Object Query Language (SOQL). Generate optimized queries from natural language, analyze query performance, and ensure best practices for governor limits and security.

Core Responsibilities

1. Natural Language → SOQL: Convert plain English requests to optimized queries
2. Query Optimization: Analyze and improve query performance
3. Relationship Queries: Build parent-child and child-parent traversals
4. Aggregate Functions: COUNT, SUM, AVG, MIN, MAX with GROUP BY
5. Security Enforcement: Ensure FLS and sharing rules compliance
6. Governor Limit Awareness: Design queries within limits

Workflow (4-Phase Pattern)

Phase 1: Requirements Gathering

Use AskUserQuestion to gather:

• What data is needed (objects, fields)
• Filter criteria (WHERE conditions)
• Sort requirements (ORDER BY)
• Record limit requirements
• Use case (display, processing, reporting)

Phase 2: Query Generation

Natural Language Examples:

Request	Generated SOQL
"Get all active accounts with their contacts"	SELECT Id, Name, (SELECT Id, Name FROM Contacts) FROM Account WHERE IsActive__c = true
"Find contacts created this month"	SELECT Id, Name, Email FROM Contact WHERE CreatedDate = THIS_MONTH
"Count opportunities by stage"	SELECT StageName, COUNT(Id) FROM Opportunity GROUP BY StageName
"Get accounts with revenue over 1M sorted by name"	SELECT Id, Name, AnnualRevenue FROM Account WHERE AnnualRevenue > 1000000 ORDER BY Name

Phase 3: Optimization

Query Optimization Checklist:

1. Selectivity: Does WHERE clause use indexed fields?
2. Field Selection: Only query needed fields (not SELECT *)
3. Limit: Is LIMIT appropriate for use case?
4. Relationship Depth: Avoid deep traversals (max 5 levels)
5. Aggregate Queries: Use for counts instead of loading all records

Phase 4: Validation & Execution

# Test query
sf data query --query "SELECT Id, Name FROM Account LIMIT 10" --target-org my-org

# Analyze query plan
sf data query --query "..." --target-org my-org --use-tooling-api --plan

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Best Practices (100-Point Scoring)

Category	Points	Key Rules
Selectivity	25	Indexed fields in WHERE, selective filters
Performance	25	Appropriate LIMIT, minimal fields, no unnecessary joins
Security	20	WITH SECURITY_ENFORCED or stripInaccessible
Correctness	15	Proper syntax, valid field references
Readability	15	Formatted, meaningful aliases, comments

Scoring Thresholds:

⭐⭐⭐⭐⭐ 90-100 pts → Production-optimized query
⭐⭐⭐⭐   80-89 pts  → Good query, minor optimizations possible
⭐⭐⭐    70-79 pts   → Functional, performance concerns
⭐⭐      60-69 pts   → Basic query, needs improvement
⭐        <60 pts    → Problematic query

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SOQL Reference

Basic Query Structure

SELECT field1, field2, ...
FROM ObjectName
WHERE condition1 AND condition2
ORDER BY field1 ASC/DESC
LIMIT number
OFFSET number

Field Selection

-- Specific fields (recommended)
SELECT Id, Name, Industry FROM Account

-- All fields (avoid in Apex - use only in Developer Console)
SELECT FIELDS(ALL) FROM Account LIMIT 200

-- Standard fields only
SELECT FIELDS(STANDARD) FROM Account

WHERE Clause Operators

Operator	Example	Notes
=	Name = 'Acme'	Exact match
!=	Status != 'Closed'	Not equal
<, >, <=, >=	Amount > 1000	Comparison
LIKE	Name LIKE 'Acme%'	Wildcard match
IN	Status IN ('New', 'Open')	Multiple values
NOT IN	Type NOT IN ('Other')	Exclude values
INCLUDES	Interests__c INCLUDES ('Golf')	Multi-select picklist
EXCLUDES	Interests__c EXCLUDES ('Golf')	Multi-select exclude

Date Literals

Literal	Meaning
TODAY	Current day
YESTERDAY	Previous day
THIS_WEEK	Current week (Sun-Sat)
LAST_WEEK	Previous week
THIS_MONTH	Current month
LAST_MONTH	Previous month
THIS_QUARTER	Current quarter
THIS_YEAR	Current year
LAST_N_DAYS:n	Last n days
NEXT_N_DAYS:n	Next n days

-- Created in last 30 days
SELECT Id FROM Account WHERE CreatedDate = LAST_N_DAYS:30

-- Modified this month
SELECT Id FROM Contact WHERE LastModifiedDate = THIS_MONTH

---

Relationship Queries

Child-to-Parent (Dot Notation)

-- Access parent fields
SELECT Id, Name, Account.Name, Account.Industry
FROM Contact
WHERE Account.AnnualRevenue > 1000000

-- Up to 5 levels
SELECT Id, Contact.Account.Owner.Manager.Name
FROM Case

Parent-to-Child (Subquery)

-- Get parent with related children
SELECT Id, Name,
       (SELECT Id, FirstName, LastName FROM Contacts),
       (SELECT Id, Name, Amount FROM Opportunities WHERE StageName = 'Closed Won')
FROM Account
WHERE Industry = 'Technology'

Relationship Names

Object	Relationship Name	Example
Account → Contacts	Contacts	(SELECT Id FROM Contacts)
Account → Opportunities	Opportunities	(SELECT Id FROM Opportunities)
Account → Cases	Cases	(SELECT Id FROM Cases)
Contact → Cases	Cases	(SELECT Id FROM Cases)
Opportunity → OpportunityLineItems	OpportunityLineItems	(SELECT Id FROM OpportunityLineItems)

Custom Object Relationships

-- Custom relationship: add __r suffix
SELECT Id, Name, Custom_Object__r.Name
FROM Another_Object__c

-- Child relationship: add __r suffix
SELECT Id, (SELECT Id FROM Custom_Children__r)
FROM Parent_Object__c

---

Aggregate Queries

Basic Aggregates

-- Count all records
SELECT COUNT() FROM Account

-- Count with alias
SELECT COUNT(Id) cnt FROM Account

-- Sum, Average, Min, Max
SELECT SUM(Amount), AVG(Amount), MIN(Amount), MAX(Amount)
FROM Opportunity
WHERE StageName = 'Closed Won'

GROUP BY

-- Count by field
SELECT Industry, COUNT(Id)
FROM Account
GROUP BY Industry

-- Multiple groupings
SELECT StageName, CALENDAR_YEAR(CloseDate), COUNT(Id)
FROM Opportunity
GROUP BY StageName, CALENDAR_YEAR(CloseDate)

HAVING Clause

-- Filter aggregated results
SELECT Industry, COUNT(Id) cnt
FROM Account
GROUP BY Industry
HAVING COUNT(Id) > 10

GROUP BY ROLLUP

-- Subtotals
SELECT LeadSource, Rating, COUNT(Id)
FROM Lead
GROUP BY ROLLUP(LeadSource, Rating)

---

Query Optimization

Indexing Strategy

Indexed Fields (Always Selective):

• Id
• Name
• OwnerId
• CreatedDate
• LastModifiedDate
• RecordTypeId
• External ID fields
• Master-Detail relationship fields
• Lookup fields (when unique)

Standard Indexed Fields by Object:

• Account: AccountNumber, Site
• Contact: Email
• Lead: Email
• Case: CaseNumber
• Opportunity: -

Selectivity Rules

A filter is selective when it returns:
- < 10% of total records for first 1 million
- < 5% of total records for additional records
- OR uses an indexed field

Optimization Patterns

-- ❌ NON-SELECTIVE (scans all records)
SELECT Id FROM Lead WHERE Status = 'Open'

-- ✅ SELECTIVE (uses index + selective filter)
SELECT Id FROM Lead
WHERE Status = 'Open'
AND CreatedDate = LAST_N_DAYS:30
LIMIT 10000

-- ❌ LEADING WILDCARD (can't use index)
SELECT Id FROM Account WHERE Name LIKE '%corp'

-- ✅ TRAILING WILDCARD (uses index)
SELECT Id FROM Account WHERE Name LIKE 'Acme%'

Query Plan Analysis

# Get query plan
sf data query \
  --query "SELECT Id FROM Account WHERE Name = 'Test'" \
  --target-org my-org \
  --use-tooling-api \
  --plan

Plan Output Interpretation:

• Cardinality: Estimated rows returned
• Cost: Relative query cost (lower is better)
• Fields: Index fields used
• LeadingOperationType: How the query starts (Index vs TableScan)

---

Security Patterns

WITH SECURITY_ENFORCED

-- Throws exception if user lacks FLS
SELECT Id, Name, Phone
FROM Account
WITH SECURITY_ENFORCED

WITH USER_MODE / SYSTEM_MODE

-- Respects sharing rules (default in Apex)
SELECT Id, Name FROM Account WITH USER_MODE

-- Bypasses sharing rules (use with caution)
SELECT Id, Name FROM Account WITH SYSTEM_MODE

In Apex: stripInaccessible

// Strip inaccessible fields instead of throwing
SObjectAccessDecision decision = Security.stripInaccessible(
    AccessType.READABLE,
    [SELECT Id, Name, SecretField__c FROM Account]
);
List<Account> safeAccounts = decision.getRecords();

---

Governor Limits

Limit	Synchronous	Asynchronous
Total SOQL Queries	100	200
Records Retrieved	50,000	50,000
Query Rows (queryMore)	2,000	2,000
Query Locator Rows	10 million	10 million

Efficient Patterns

-- ❌ Query all, filter in Apex
SELECT Id, Name FROM Account
-- Then filter 50,000 records in Apex

-- ✅ Filter in SOQL
SELECT Id, Name FROM Account
WHERE Industry = 'Technology' AND IsActive__c = true
LIMIT 1000

-- ❌ Multiple queries in loop
for (Contact c : contacts) {
    Account a = [SELECT Name FROM Account WHERE Id = :c.AccountId];
}

-- ✅ Single query with Map
Map<Id, Account> accounts = new Map<Id, Account>(
    [SELECT Id, Name FROM Account WHERE Id IN :accountIds]
);

---

SOQL FOR Loops

// For large datasets - doesn't load all into heap
for (Account acc : [SELECT Id, Name FROM Account WHERE Industry = 'Technology']) {
    // Process one record at a time
    // Governor: Uses queryMore internally (200 at a time)
}

// With explicit batch size
for (List<Account> accs : [SELECT Id, Name FROM Account]) {
    // Process 200 records at a time
}

---

Advanced Features

Polymorphic Relationships (What)

-- Query polymorphic fields
SELECT Id, What.Name, What.Type
FROM Task
WHERE What.Type IN ('Account', 'Opportunity')

-- TYPEOF for conditional fields
SELECT
    TYPEOF What
        WHEN Account THEN Name, Phone
        WHEN Opportunity THEN Name, Amount
    END
FROM Task

Semi-Joins and Anti-Joins

-- Semi-join: Records that HAVE related records
SELECT Id, Name FROM Account
WHERE Id IN (SELECT AccountId FROM Contact)

-- Anti-join: Records that DON'T HAVE related records
SELECT Id, Name FROM Account
WHERE Id NOT IN (SELECT AccountId FROM Opportunity)

Format in Aggregate Queries

-- Format currency/date in results
SELECT FORMAT(Amount), FORMAT(CloseDate)
FROM Opportunity

convertCurrency()

-- Convert to user's currency
SELECT Id, convertCurrency(Amount)
FROM Opportunity

---

CLI Commands

Execute Query

# Basic query
sf data query --query "SELECT Id, Name FROM Account LIMIT 10" --target-org my-org

# JSON output
sf data query --query "SELECT Id, Name FROM Account" --target-org my-org --json

# CSV output
sf data query --query "SELECT Id, Name FROM Account" --target-org my-org --result-format csv

Bulk Query

# For large datasets
sf data query --query "SELECT Id, Name FROM Account" --target-org my-org --bulk

Query Plan

sf data query \
  --query "SELECT Id FROM Account WHERE Name = 'Test'" \
  --target-org my-org \
  --use-tooling-api \
  --plan

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Cross-Skill Integration

Skill	When to Use	Example
sf-apex	Embed queries in Apex	Skill(skill="sf-apex", args="Create service with SOQL query for accounts")
sf-data	Execute queries against org	Skill(skill="sf-data", args="Query active accounts from production")
sf-debug	Analyze query performance	Skill(skill="sf-debug", args="Analyze slow query in debug logs")
sf-lwc	Generate wire queries	Skill(skill="sf-lwc", args="Create component with wired account query")

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Natural Language Examples

Request	SOQL
"Get me all accounts"	SELECT Id, Name FROM Account LIMIT 1000
"Find contacts without email"	SELECT Id, Name FROM Contact WHERE Email = null
"Accounts created by John Smith"	SELECT Id, Name FROM Account WHERE CreatedBy.Name = 'John Smith'
"Top 10 opportunities by amount"	SELECT Id, Name, Amount FROM Opportunity ORDER BY Amount DESC LIMIT 10
"Accounts in California"	SELECT Id, Name FROM Account WHERE BillingState = 'CA'
"Contacts with @gmail emails"	SELECT Id, Name, Email FROM Contact WHERE Email LIKE '%@gmail.com'
"Opportunities closing this quarter"	SELECT Id, Name, CloseDate FROM Opportunity WHERE CloseDate = THIS_QUARTER
"Cases opened in last 7 days"	SELECT Id, Subject FROM Case WHERE CreatedDate = LAST_N_DAYS:7
"Total revenue by industry"	SELECT Industry, SUM(AnnualRevenue) FROM Account GROUP BY Industry
"Accounts with more than 5 contacts"	SELECT Id, Name, (SELECT Id FROM Contacts) FROM Account + filter in Apex

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Dependencies

Required: Target org with sf CLI authenticated

Recommended:

• sf-debug (for query plan analysis)
• sf-apex (for embedding in Apex code)

Install: /plugin install github:Jaganpro/sf-skills/sf-soql

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Documentation

Document	Description
soql-reference.md	Complete SOQL syntax reference
cli-commands.md	SF CLI query commands
anti-patterns.md	Common mistakes and how to avoid them
selector-patterns.md	Query abstraction patterns (vanilla Apex)

Templates

Template	Description
basic-queries.soql	Basic SOQL syntax examples
aggregate-queries.soql	COUNT, SUM, GROUP BY patterns
relationship-queries.soql	Parent-child traversals
optimization-patterns.soql	Selectivity and indexing
selector-class.cls	Selector class template
bulkified-query-pattern.cls	Map-based bulk lookups

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Credits

See CREDITS.md for acknowledgments of community resources that shaped this skill.

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License

MIT License. See LICENSE file. Copyright (c) 2024-2025 Jag Valaiyapathy