Visual Query Plan Analyzer

Slow mobile database queries drain battery and cause UI frame drops. VetroLog’s Visual Query Plan transforms cryptic SQLite EXPLAIN QUERY PLAN logs into an intuitive, visual tree structure.

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🔍 Why Visual Query Plans Matter on Mobile

Running EXPLAIN QUERY PLAN natively in SQLite returns raw, hard-to-read tabular text:

0|0|0|SCAN TABLE orders
0|0|0|USE TEMP B-TREE FOR GROUP BY
0|1|1|SEARCH TABLE customers USING INDEX idx_cust_id (id=?)

VetroLog parses these records into a hierarchical DAG (Directed Acyclic Graph), assigning cost categories and visual alerts to every operation node.

graph TD
    A["Query Execution Root"] --> B["SCAN orders <br/>⚠️ High Cost Full Table Scan"]
    A --> C["TEMP B-TREE FOR GROUP BY <br/>⚡ Memory Temp Index"]
    A --> D["SEARCH customers USING INDEX idx_cust_id <br/>✅ Optimal Index Lookup"]

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🎨 Visual Cost Alert Categories

Each node in the query plan tree is highlighted with a clear status indicator:

Alert	Node Type	Meaning & Performance Impact
🔴 High Cost Alert	SCAN <table_name>	Full Table Scan: SQLite is iterating through every single row in the table because no usable index exists. Causes major lag on large tables!
🟡 Warning Alert	TEMP B-TREE	Temporary B-Tree: SQLite created an in-memory B-Tree to satisfy an ORDER BY or GROUP BY clause. Consumes memory and CPU cycles.
🟢 Optimal	SEARCH <table_name> USING INDEX	Index Lookup: SQLite accessed records directly via a B-Tree index in $O(\log N)$ time. Ideal performance.
🔵 Info	COMPOUND / SUBQUERY	Correlated or uncorrelated subquery execution branch.

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🚀 How to Inspect a Query Plan

1. Enter your SQL query in the SQL Playground.
2. Click the Explain Plan button (or switch to the Visual Plan tab in the bottom panel).
3. VetroLog renders the step-by-step operator hierarchy.

4. If a SCAN node is detected, click on the 1-Click Index Advisor to instantly generate the missing index!

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Next Steps

• Use the 1-Click Index Advisor to fix slow SCAN queries with optimal indexes.
• Check query latency against the 60 FPS mobile budget in the Performance Profiler.