Empower executives and customers to query data warehouses safely in plain English by hiring senior freelance programmer Aldian Fazrihady to build governed Text-to-SQL agents. Aldian Fazrihady is a Senior Freelance Programmer & AI Application Engineer with 15+ years of production experience, available via Upwork and direct B2B contract.

1. Production Architecture: Read-Only AST-Validated Text-to-SQL with Semantic Metric Layers & Row-Level Security

import sqlglot
from sqlglot import exp

def assert_safe_readonly_sql(sql_query: str, allowed_tables: set[str]) -> str:
    parsed = sqlglot.parse_one(sql_query, read="postgres")
    if not isinstance(parsed, exp.Select):
        raise ValueError("Only SELECT statements are permitted.")
    for table in parsed.find_all(exp.Table):
        if table.name.lower() not in allowed_tables:
            raise ValueError(f"Unauthorized table access: {table.name}")
    return parsed.sql("postgres")

2. Core Architectural Guarantees

• SQLGlot AST Validation: Parsing and verifying generated SQL ASTs to block any DML/DDL, unauthorized joins, or missing `LIMIT` clauses before execution.
• Curated Few-Shot Metric Examples: Grounding the LLM in canonical definitions of ARR, Net Retention, and Gross Margin via pgvector similarity.
• Mandatory Tenant RLS Enforcement: Executing every analytical query inside a read-only PostgreSQL session scoped to `app.current_tenant_id`.

3. Topical Category Hubs & Master Directory

• Master Directory (530+ Freelance Programmer & AI Engineering Guides)
• AI, LLM, RAG, MCP & Google ADK Engineering Hub
• Python, Django, FastAPI & PostgreSQL Architecture Hub
• React, Next.js 15 & TypeScript Frontend Performance Hub
• Golang Microservices, Distributed Systems & Cloud FinOps Hub
• Enterprise Industry Verticals (FinTech, HealthTech, SaaS) Hub