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Practical notes: Apache Doris 4.1: Unified Storage and Retrieval for AI & Search

Operable walkthrough of Practical notes: Apache Doris 4.1: Unified Storage and Retrieval for AI & Search: contracts, checks, and drop-in code slots for teams shipping this pattern.

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The following notes reconstruct a practical path around “Apache Doris 4.1: Unified Storage and Retrieval for AI & Search”. Emphasis stays on contracts, checks, and drop-in code placeholders rather than motivational framing. When working through the Overview stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

1. AI & Search

The 1 AI Search stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

A. Vector Search

The A Vector Search stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

CREATE TABLE sift_1M (
  id int NOT NULL,
  embedding array<float>  NOT NULL  COMMENT "",
  INDEX ann_index (embedding) USING ANN PROPERTIES(
      "index_type"="ivf",
      "metric_type"="l2_distance",
      "dim"="128",
      "nlist"="1024"
  )
) ENGINE=OLAP
DUPLICATE KEY(id) COMMENT "OLAP"
DISTRIBUTED BY HASH(id) BUCKETS 1
PROPERTIES (
  "replication_num" = "1"
);
CREATE TABLE for_ivf_on_disk (
  id BIGINT NOT NULL,
  embedding ARRAY<FLOAT> NOT NULL,
  INDEX idx_emb (embedding) USING ANN PROPERTIES (
    "index_type"="ivf_on_disk",
      "metric_type"="l2_distance",
      "dim"="128",
      "nlist"="1024"
  )
) ENGINE=OLAP
DUPLICATE KEY(id)
DISTRIBUTED BY HASH(id) BUCKETS 8
PROPERTIES ("replication_num" = "1");
CREATE TABLE product_quant (
  id BIGINT NOT NULL,
  embedding ARRAY<FLOAT> NOT NULL,
  INDEX idx_emb (embedding) USING ANN PROPERTIES (
    "index_type"="ivf_on_disk",
      "metric_type"="l2_distance",
      "dim"="128",
      "nlist"="1024",
      "quantizer"="pq",
      "pq_m"=64,
      "pq_nbits"=8
  )
) ENGINE=OLAP
DUPLICATE KEY(id)
DISTRIBUTED BY HASH(id) BUCKETS 8
PROPERTIES ("replication_num" = "1");

B. The search() Function: Unified Text Search and Analytics in SQL

The B The search Function stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move. The B The search Function stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

-- Multi-condition: TERM + PHRASE + NOT evaluated in a single pass
SELECT request_id, error_msg, latency_ms
FROM inference_logs
WHERE search('
  level:ERROR
  AND error_msg:"CUDA out of memory"
  AND NOT module:healthcheck
  AND model_name:gpt*
')
  AND log_time > NOW() - INTERVAL 1 HOUR
ORDER BY latency_ms DESC LIMIT 100;
​
-- BM25 relevance scoring
SELECT request_id, error_msg, score() AS relevance
FROM inference_logs
WHERE search('error_msg:"memory allocation failed" OR error_msg:"CUDA error"')
ORDER BY relevance DESC LIMIT 20;
​
-- Nested search: query inside a VARIANT array
SELECT * FROM agent_logs
WHERE search('NESTED(steps, status:error AND tool:code_exec)');
​
-- search + aggregation: filter and analyze in one query
SELECT model_name, COUNT(*) AS error_count,
       PERCENTILE_APPROX(latency_ms, 0.99) AS p99_latency
FROM inference_logs
WHERE search('level:ERROR AND error_msg:"CUDA out of memory"')
  AND log_time > NOW() - INTERVAL 1 HOUR
GROUP BY model_name ORDER BY error_count DESC;

C. Native 100MB JSON Document Storage for Long-Context AI Conversations

For the C Native 100MB JSON stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

D. Segment V3: Metadata Decoupling for Wide Tables

For the D Segment V3 Metadata stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

CREATE TABLE table_v3 (
    id BIGINT,
    data VARIANT
)
DISTRIBUTED BY HASH(id) BUCKETS 32
PROPERTIES (
    "storage_format" = "V3"
);

E. Sparse Column Optimization: Sparse Sharding and Sparse Cache

For the E Sparse Column Optimization stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap. For the E Sparse Column Optimization stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

CREATE TABLE user_feature_wide (
    uid BIGINT,
    features VARIANT<
        'user_id' : BIGINT,
        'region' : STRING,
        properties(
            'variant_max_subcolumns_count' = '2048',
            'variant_sparse_hash_shard_count' = '32'
        )
    >
)
DUPLICATE KEY(uid)
DISTRIBUTED BY HASH(uid) BUCKETS 32
PROPERTIES (
    "storage_format" = "V3"
);

F. DOC Mode: Faster Writes and Efficient Full-Document Retrieval

When working through the F DOC Mode Faster stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface.

CREATE TABLE trace_archive (
    ts DATETIME,
    trace_id STRING,
    span VARIANT<
        'service_name' : STRING,
        properties(
            'variant_enable_doc_mode' = 'true',
            'variant_doc_materialization_min_rows' = '100000',
            'variant_doc_hash_shard_count' = '32'
        )
    >
)
DUPLICATE KEY(ts, trace_id)
DISTRIBUTED BY HASH(trace_id) BUCKETS 32
PROPERTIES (
    "storage_format" = "V3"
);

2. Faster OLAP

When working through the 2 Faster OLAP stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface.

Multi-Table Analytics

When working through the Multi-Table Analytics stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface. When working through the Multi-Table Analytics stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

Wide-Table Analytics

The Wide-Table Analytics stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

A. Aggregation Pushdown Through JOIN

The A Aggregation Pushdown Through stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

B. Grouping Sets Optimization

The B Grouping Sets Optimization stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move. The B Grouping Sets Optimization stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

C. Nested Column Pruning

For the C Nested Column Pruning stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

D. Condition Cache

For the D Condition Cache stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

SELECT * FROM orders WHERE region = 'ASIA';
SELECT count(*) FROM orders WHERE region = 'ASIA';

E. Query Cache: Reusing Intermediate Aggregation Results

For the E Query Cache Reusing stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap. For the E Query Cache Reusing stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

SELECT region, SUM(revenue) FROM orders WHERE dt = '2024-01-01' GROUP BY region;

F. CASE WHEN Optimization

When working through the F CASE WHEN Optimization stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface.

3. Compute-Storage Separation

When working through the 3 Compute-Storage Separation stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface.

A. File Cache Improvements

When working through the A File Cache Improvements stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface. When working through the A File Cache Improvements stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

mysql> select * from information_schema.file_cache_info where TABLET_ID = 1761571031445;
+----------------------------------+---------------+-------+--------+-------------+-----------------+---------------+
| HASH                             | TABLET_ID     | SIZE  | TYPE  | REMOTE_PATH | CACHE_PATH       | BE_ID         |
+----------------------------------+---------------+-------+--------+-------------+-----------------+---------------+
| 468448215c52334ae5bee147259b1027 | 1761571031445 | 15120 | index | | /mnt/disk1/project/filecache | 1761571031251 |
| 71bb73d34cd8ffe280b16dd329df5ba1 | 1761571031445 | 13117 | index | | /mnt/disk1/project/filecache | 1761571031251 |
| 77c6b69d1a7c4fe740a11bab5c1bbaa3 | 1761571031445 | 12249 | index | | /mnt/disk1/project/filecache | 1761571031251 |
+----------------------------------+---------------+-------+--------+-------------+-----------------------------------------------------------------------------+---------------+
SELECT be_id, tablet_id, type, SUM(size) AS cache_bytes
    FROM information_schema.file_cache_info
    WHERE tablet_id = 1761571031445
    GROUP BY be_id, tablet_id, type
    ORDER BY cache_bytes DESC;

B. Elastic Scaling, Cold Queries, and Other Improvements

The B Elastic Scaling Cold stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

4. Data Lakehouse

The 4 Data Lakehouse stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

A. Lakehouse Lifecycle Management

The A Lakehouse Lifecycle Management stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move. The A Lakehouse Lifecycle Management stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

B. Lakehouse Query Performance

For the B Lakehouse Query Performance stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

C. Federated Analytics Usability

For the C Federated Analytics Usability stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

5. Batch Processing

For the 5 Batch Processing stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap. For the 5 Batch Processing stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

A. MERGE INTO

When working through the A MERGE INTO stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface.

MERGE INTO target t
USING source s
ON t.id = s.id
WHEN MATCHED THEN
    UPDATE SET t.value = s.value
WHEN NOT MATCHED THEN
    INSERT (id, value) VALUES (s.id, s.value);

B. Enhanced Spill-to-Disk

When working through the B Enhanced Spill-to-Disk stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface.

6. Usability Enhancements

When working through the 6 Usability Enhancements stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Measure recall on a fixed question set before tuning prompts. Prompt churn rarely fixes a weak retrieval surface. When working through the 6 Usability Enhancements stage, write down the contract first: required inputs, success signal, and what happens on partial failure. That checklist keeps later code changes honest. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

A. Execution Engine Extensions

The A Execution Engine Extensions stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

SELECT user_id, tag
FROM user_profile,
UNNEST(tags) AS t(tag);
WITH RECURSIVE org_tree AS (
    SELECT id, parent_id, name
    FROM org
    WHERE parent_id IS NULL
​
    UNION ALL
​
    SELECT o.id, o.parent_id, o.name
    FROM org o
    JOIN org_tree t ON o.parent_id = t.id
)
SELECT * FROM org_tree;
SELECT t1.ts, t1.value, t2.price
FROM trades t1
ASOF JOIN prices t2
ON t1.symbol = t2.symbol
AND t1.ts >= t2.ts;

B. Data Ingestion and Write Path Improvements

The B Data Ingestion and stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Separate chunking policy from retrieval policy. Changing one should not force a rewrite of the other when quality metrics move.

C. Write and Update Model Improvements

The C Write and Update stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Document the happy path and the recovery path together. Retries, human gates, and dead-letter handling are part of the product, not later polish. Budget tokens per turn and per session. Agentic tools expand context aggressively; hard caps keep demos from becoming surprise invoices. The C Write and Update stage works best when treated as a measurable surface. Capture one golden transcript, one failure case, and the rollback note before expanding scope. Treat this stage as a contract between inputs and validated outputs. Name the artifacts, define success checks, and refuse silent partial completion.

D. TIMESTAMPTZ: Native Time Zone Support

For the D TIMESTAMPTZ Native Time stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Record timings and token or query cost next to functional results. Cost visibility early prevents surprise bills when the path moves from demo to shared environments. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

Summary

For the Summary stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state. Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph. Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

Operational checklist

For the Operational checklist stage, define the inputs, the owner of the step, and the exit criteria before changing code. Operators should be able to re-run the step from a known checkpoint without guessing hidden state.

Prefer small, testable units over sprawling scripts. When a step fails, the failure should point at a single responsibility rather than a tangled pipeline.

Cite the passages that actually grounded the answer. Without citations, operators cannot tell hallucination from an indexing gap.

Track cost and latency beside quality. A slightly worse answer that costs 10x less may be the right production trade.

Pin dependency versions and record the image digest that ran the demo. Reproducibility beats tribal knowledge.

Keep configuration outside application code. Environment files, secret stores, and feature flags belong in one place operators can audit without reading the whole graph.

Before promoting the stack, freeze versions, capture a golden transcript for the critical path, and confirm rollback steps. Shared environments need rate limits, tenancy checks, and a clear owner for secret rotation. Prefer boring reliability over clever one-off demos.

Batch note for 14edffdb7bab: keep provider keys out of the repo, set a per-session token ceiling, and store transcripts next to the eval fixtures so later model swaps stay comparable.