Day 6 Data Structure Codex AI Architect

Data design tasks based on Codex Client Workspace

Differences in data structure understanding, terminology fragmentation, and change impact propagation issues that startups face during the MVP development stage
This is a practical AI collaboration task board that automatically analyzes and resolves using Codex.

Day 6 Startup MVP Tasks

From blank screens to prototyping, error debugging, and refactoring for code readability — experience a development workflow that turns Codex into a capable pair programmer.

TASK 1
Task 1

Task 1. Practice resolving gaps in data structure understanding

Task 01: Alignment of data structure between planning and development (Data Structure Alignment)

By deriving key entities and relationships (Mermaid ERD) from planning meeting minutes written in natural language, the gap in data model understanding between planners and developers is resolved with AI.

target numberCompletion of ERD schema and data structure definition
core toolsCodex Client Workspace
scope of practiceData Structure Alignment
Step 1 📂 Prepare meeting minutes file (day6_meeting_notes.md) and upload Codex
Step 2 🔍 Request Codex to derive entities and create Mermaid ERD
ERD Entity Mapping Data Alignment
expected output erd-schema.md (Data Specification and ERD)
Task 1 Entry to the lab
TASK 2
Task 2

Task 2. Error resolution assistant practice

Task 02: Reading console logs and building defense code (AI Debug Assistant)

It pinpoints the exact line number and preemptive defense code in the crash log that references the undefined property that paralyzes browser rendering.

target numberDebugging of error-causing logic completed
core toolsCodex Client Workspace
scope of practiceAsynchronous Debugging
Step 1 📁 Prepare error file (day6_debug_source.js) and compare error logs
Step 2 🔍 Request Codex to determine the cause and apply a conditional exception guard patch
TypeError Optional Chaining Stack Trace
expected output day6_debug_solution.js (Stable reaction script)
Task 2 Entry to the lab
TASK 3
Task 3

Task 3. Practice improving code

Task 03: Source duplicate abbreviation and naming correction (Code Refactoring)

Unstructured HTML binder syntax produced through copy-and-paste is commonized as a template function, and ambiguous temporary variable names are organized into a working vocabulary.

target numberCommon utility of duplicate markup
core toolsCodex Client Workspace
scope of practiceCode Refactoring & Convention
Step 1 📂 Prepare and upload messy source code (day6_dirty_code.js)
Step 2 🔄 Instruct Codex to refactor to remove duplicates and convert readable names
Refactoring Clean Code Naming standard
expected output day6_clean_code.js (Improved readability source code)
Task 3 Entry to the lab
🚀 In-depth Mission — AI-based software development course
MISSION 1
Mission 1

Mission 1. Design decision recording practice

Mission 01: Automatic creation of Design Decision Log (Record Why)

By writing the database normalization and architecture decision background into a Design Decision Log standardized in Codex, duplicate discussions and design mistakes are prevented when new team members join.

target numberComplete design decision record document (DDL)
core toolsCodex Client Workspace
scope of practiceDesign Decision Log & Knowledge Mgmt
Step 1 📂 Preparation of technical design meeting conversation transcript (tech-design-meeting.md)
Step 2 🔍 Request Codex to standardize resolution items, background reasons, and alternative review
Decision Log Architecture Knowledge Mgmt
expected output design-decision-log.md (Decision record document)
Mission 1 Lab Entry
MISSION 2
Mission 2

Mission 2. Exception scenario discovery practice

Mission 02: Derive all concurrency and integrity edge cases (Edge Case Discovery)

Edge cases such as concurrency errors, referential integrity collapse, and hard delete failures that may occur in the defined DB schema and foreign key reference structure are discovered in advance using Codex.

target numberCompletion of exception scenario report and response plan
core toolsCodex Client Workspace
scope of practiceEdge Case Discovery & Integrity Guard
Step 1 📂 Preparation of DB physical schema definition (database-schema.md)
Step 2 🛡️ Derive all concurrency and integrity exception cases and establish countermeasures with Codex
Edge Cases Concurrency Soft Delete
expected output edge-case-analysis.md (Exception scenario report)
Mission 2 Lab Entry