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docs: standardize fanout terminology (#218)

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2
docs-site/components/semantic-layer-flow.tsx
View file

@ -253,7 +253,7 @@ const engine: EngineNode = {
},
{
index: 3,
title: "Detect fan-out",
title: "Detect fanout",
detail: "group measures by source, flag chasm traps",
},
{

16
docs-site/content/docs/concepts/semantic-layer-internals.mdx
View file

@ -8,7 +8,7 @@ import { SemanticLayerFlow } from "@/components/semantic-layer-flow";
**ktx**'s semantic layer is a compiler that turns intent into SQL. The agent
declares _what_ it wants - measures, dimensions, filters - in a small
semantic query. **ktx** figures out the _how_: which tables to join, what
grain to aggregate at, how to keep fan-out from inflating measures, and
grain to aggregate at, how to keep fanout from inflating measures, and
what dialect the warehouse speaks.
This page covers four mechanics:
@ -16,7 +16,7 @@ This page covers four mechanics:
- The semantic query contract agents send to the compiler.
- The planner steps that turn a semantic query into SQL.
- The join graph that backs those steps, and how it's built.
- The fan-out failure mode the compiler is designed to prevent.
- The fanout failure mode the compiler is designed to prevent.
## Imperative SQL vs declarative semantic querying
@ -84,14 +84,14 @@ same ordered steps before any SQL is emitted.
2. **Pick an anchor and build the join tree.** Choose the largest measure
source as the root, then run a shortest-path search across the typed
join graph to reach every required source.
3. **Detect fan-out.** Group measures by their owning source. If more
3. **Detect fanout.** Group measures by their owning source. If more
than one group exists, the planner marks the query as a chasm trap
and switches to aggregate-locality compilation.
4. **Classify filters.** Split predicates into row-level (`WHERE`) and
aggregate-level (`HAVING`) based on whether they reference a measure.
5. **Generate SQL.** Emit Postgres-shaped SQL with the right shape:
single-source aggregation when the query is safe, per-source CTEs
when fan-out is present.
when fanout is present.
6. **Transpile to the target dialect.** Run the result through `sqlglot`
so the warehouse receives syntax it understands.
@ -107,7 +107,7 @@ inverted, so the planner can traverse from any anchor.
| Relationship | Planning impact |
|--------------|-----------------|
| `many_to_one` | Safe direction for adding dimensions |
| `one_to_many` | Multiplies measures and triggers fan-out handling |
| `one_to_many` | Multiplies measures and triggers fanout handling |
| `one_to_one` | Safe in either direction when keys match |
| Equal-cost paths | Treated as ambiguous; aliases or explicit joins resolve them |
@ -286,9 +286,9 @@ inference. Each input contributes a different kind of authority.
</div>
</div>
## Fan-out and aggregate locality
## Fanout and aggregate locality
Fan-out is the classic analytics failure mode. Two fact tables join to a
Fanout is the classic analytics failure mode. Two fact tables join to a
shared dimension. A naive query joins them all together first, so each
row from one fact is multiplied by the matching rows from the other.
Measures duplicate, numbers go wrong, and the agent doesn't notice.
@ -336,5 +336,5 @@ different from what the agent first proposed.
| Explain the semantic query shape | The semantic query contract | [ktx sl](/docs/cli-reference/ktx-sl) |
| Describe what the planner does between query and SQL | What the planner does | [ktx sl](/docs/cli-reference/ktx-sl) |
| Explain why **ktx** asks for grain and relationship types | The join graph | [Writing context](/docs/guides/writing-context) |
| Diagnose duplicated measures after a join | Fan-out and aggregate locality | [ktx sl](/docs/cli-reference/ktx-sl) |
| Diagnose duplicated measures after a join | Fanout and aggregate locality | [ktx sl](/docs/cli-reference/ktx-sl) |
| Describe how semantic context stays current | Building and maintaining the graph | [Reviewing Context](/docs/guides/reviewing-context) |

4
docs-site/content/docs/concepts/the-context-layer.mdx
View file

@ -156,7 +156,7 @@ joins:
relationship: many_to_one
```
For how the compiler walks the join graph, handles fan-out, and transpiles
For how the compiler walks the join graph, handles fanout, and transpiles
dialects, read [Semantic querying](/docs/concepts/semantic-layer-internals).
## Wiki pages
@ -240,7 +240,7 @@ models every time the warehouse changes.
| **Surface** | Indexed docs and chats | Modeling language or runtime | YAML and Markdown files |
| **Data-stack awareness** | None - treats data tools as text | High for declared metrics, none for the surrounding warehouse | Built in: scans schemas, dbt, BI tools, and query history |
| **Maintenance** | Manual page authoring | Manual modeling, model-per-change | Auto-maintained: reconciles evidence with accepted files |
| **SQL safety** | None - generates plausible text | Compiled, dialect-correct | Compiled with join-graph and fan-out handling |
| **SQL safety** | None - generates plausible text | Compiled, dialect-correct | Compiled with join-graph and fanout handling |
| **Agent edit loop** | Text-only | Tied to the modeling workflow | First-class: patch files, validate, review diffs |
If you already use MetricFlow, LookML, dbt, or BI tools, **ktx** can ingest that

2
docs/terminology.md
View file

@ -56,7 +56,7 @@ referent (e.g., body of a `Semantic sources` page, or `sourceName` as a CLI arg)
| Wiki surface as a whole | **wiki** | "wiki context" |
| A single Markdown file | **wiki page** | — |
| YAML vs Markdown contrast | **wiki Markdown** (only when contrasting with **semantic source YAML**) | — |
| Joins multiplying rows (generic) | **fan-out** | — |
| Joins multiplying rows (generic) | **fanout** | — |
| The two named patterns | **chasm trap** / **fan trap** | — |
| Casual gloss in user prose | **double-count** | (avoid in technical/internals prose) |

2
packages/cli/src/context/ingest/local-adapters.test.ts
View file

@ -76,7 +76,7 @@ describe('local ingest adapters', () => {
expect(looker?.fetch).toBeTypeOf('function');
});
it('returns the explicit Metabase fan-out boundary before runner construction', async () => {
it('returns the explicit Metabase fanout boundary before runner construction', async () => {
const metabase = createDefaultLocalIngestAdapters(project).find((adapter) => adapter.source === 'metabase');
await expect(localPullConfigForAdapter(project, metabase!, 'warehouse')).rejects.toThrow(

2
packages/cli/src/context/ingest/local-ingest.ts
View file

@ -336,7 +336,7 @@ export async function runLocalMetabaseIngest(
options: RunLocalMetabaseIngestOptions,
): Promise<LocalMetabaseFanoutResult> {
if ((options as RunLocalMetabaseIngestOptions & { sourceDir?: string }).sourceDir) {
throw new Error('source-dir uploads are not supported for the Metabase fan-out adapter');
throw new Error('source-dir uploads are not supported for the Metabase fanout adapter');
}
const metabaseConnectionId = safeSegment('metabase connection id', options.metabaseConnectionId);

6
packages/cli/src/context/ingest/local-metabase-ingest.test.ts
View file

@ -148,7 +148,7 @@ describe('runLocalMetabaseIngest', () => {
).rejects.toThrow('no sync-enabled mappings with a target connection');
});
it('seeds yaml-only Metabase mappings before the unhydrated fan-out preflight', async () => {
it('seeds yaml-only Metabase mappings before the unhydrated fanout preflight', async () => {
project.config.connections['prod-metabase'].mappings = {
databaseMappings: { '1': 'warehouse_a' },
syncEnabled: { '1': true },
@ -172,7 +172,7 @@ describe('runLocalMetabaseIngest', () => {
]);
});
it('rejects source-dir uploads through the Metabase fan-out runner', async () => {
it('rejects source-dir uploads through the Metabase fanout runner', async () => {
await expect(
runLocalMetabaseIngest({
project,
@ -181,7 +181,7 @@ describe('runLocalMetabaseIngest', () => {
agentRunner: new TestAgentRunner(),
sourceDir: tempDir,
} as Parameters<typeof runLocalMetabaseIngest>[0] & { sourceDir: string }),
).rejects.toThrow('source-dir uploads are not supported for the Metabase fan-out adapter');
).rejects.toThrow('source-dir uploads are not supported for the Metabase fanout adapter');
});
it('reports partial failure when a child job fails', async () => {

2
packages/cli/src/ingest.test-utils.ts
View file

@ -533,7 +533,7 @@ export async function runPublicMetabaseSyncModeCase(tempDir: string, input: Sync
).resolves.toBe(0);
expect(io.stderr()).toContain('Metabase ingest: prod-metabase');
expect(io.stdout()).toContain('Metabase fan-out: all_succeeded');
expect(io.stdout()).toContain('Metabase fanout: all_succeeded');
expect(io.stdout()).toContain(`target=warehouse_a database=1 status=done job=${jobId}`);
const report = await getLocalIngestStatus(project, jobId);

32
packages/cli/src/ingest.test.ts
View file

@ -346,7 +346,7 @@ describe('runKtxIngest', () => {
);
});
it('routes metabase scheduled pulls to the fan-out runner and prints child summaries', async () => {
it('routes metabase scheduled pulls to the fanout runner and prints child summaries', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo();
@ -397,13 +397,13 @@ describe('runKtxIngest', () => {
),
).resolves.toBe(0);
expect(io.stdout()).toContain('Metabase fan-out: all_succeeded');
expect(io.stdout()).toContain('Metabase fanout: all_succeeded');
expect(io.stdout()).toContain('warehouse_a');
expect(io.stdout()).toContain('metabase-child-1');
expect(io.stderr()).toContain('Metabase ingest: prod-metabase');
});
it('returns a non-zero code when Metabase fan-out has failed children', async () => {
it('returns a non-zero code when Metabase fanout has failed children', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo();
@ -467,13 +467,13 @@ describe('runKtxIngest', () => {
),
).resolves.toBe(1);
expect(io.stdout()).toContain('Metabase fan-out: partial_failure');
expect(io.stdout()).toContain('Metabase fanout: partial_failure');
expect(io.stdout()).toContain('Failed tasks: 1');
expect(io.stdout()).toContain('status=error');
expect(io.stderr()).toContain('Metabase ingest: prod-metabase');
});
it('prints Metabase fan-out progress before the final summary', async () => {
it('prints Metabase fanout progress before the final summary', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo();
@ -548,11 +548,11 @@ describe('runKtxIngest', () => {
expect(io.stderr()).toContain('Targets: 1 mapped database');
expect(io.stderr()).toContain('- database=1 target=warehouse_a status=running job=metabase-child-1');
expect(io.stderr()).toContain('- database=1 target=warehouse_a status=done job=metabase-child-1');
expect(io.stdout()).toContain('Metabase fan-out: all_succeeded');
expect(io.stdout()).toContain('Metabase fanout: all_succeeded');
expect(io.stdout()).not.toContain('status=running job=metabase-child-1');
});
it('writes metabase fan-out progress to stderr and final result to stdout', async () => {
it('writes metabase fanout progress to stderr and final result to stdout', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo({ isTTY: true });
@ -592,11 +592,11 @@ describe('runKtxIngest', () => {
expect(io.stderr()).toContain('Metabase ingest: prod-metabase');
expect(io.stderr()).toContain('status=running job=metabase-child-1');
expect(io.stdout()).toContain('Metabase fan-out: all_succeeded');
expect(io.stdout()).toContain('Metabase fanout: all_succeeded');
expect(io.stdout()).not.toContain('status=running job=metabase-child-1');
});
it('emits structured progress for Metabase fan-out without writing progress to JSON output', async () => {
it('emits structured progress for Metabase fanout without writing progress to JSON output', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo();
@ -655,7 +655,7 @@ describe('runKtxIngest', () => {
expect(io.stderr()).not.toContain('Metabase ingest: prod-metabase');
});
it('emits structured child ingest progress during Metabase fan-out', async () => {
it('emits structured child ingest progress during Metabase fanout', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo();
@ -766,7 +766,7 @@ describe('runKtxIngest', () => {
expect(io.stderr()).not.toContain('Metabase ingest: prod-metabase');
});
it('runs Metabase scheduled ingest through the public CLI command path with real fan-out', async () => {
it('runs Metabase scheduled ingest through the public CLI command path with real fanout', async () => {
const projectDir = join(tempDir, 'metabase-cli-project');
await writeWarehouseConfig(projectDir);
await writeFile(
@ -838,7 +838,7 @@ describe('runKtxIngest', () => {
expect(io.stderr()).toContain('Metabase ingest: prod-metabase');
expect(io.stderr()).toContain('Targets: 2 mapped databases');
expect(io.stdout()).toContain('Metabase fan-out: all_succeeded');
expect(io.stdout()).toContain('Metabase fanout: all_succeeded');
expect(io.stdout()).toContain('Source: prod-metabase');
expect(io.stdout()).toContain('Children: 2');
expect(io.stdout()).toContain('target=warehouse_a database=1 status=done job=metabase-child-1');
@ -893,7 +893,7 @@ describe('runKtxIngest', () => {
});
});
it('prints metabase fan-out JSON results', async () => {
it('prints metabase fanout JSON results', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo();
@ -967,7 +967,7 @@ describe('runKtxIngest', () => {
expect(io.stderr()).toBe('');
});
it('rejects source-dir uploads through the metabase fan-out route', async () => {
it('rejects source-dir uploads through the metabase fanout route', async () => {
const projectDir = join(tempDir, 'project');
await writeMetabaseConfig(projectDir);
const io = makeIo();
@ -985,13 +985,13 @@ describe('runKtxIngest', () => {
io.io,
{
runLocalMetabaseIngest: async () => {
throw new Error('fan-out should not be called');
throw new Error('fanout should not be called');
},
},
),
).resolves.toBe(1);
expect(io.stderr()).toContain('source-dir uploads are not supported for the Metabase fan-out adapter');
expect(io.stderr()).toContain('source-dir uploads are not supported for the Metabase fanout adapter');
expect(io.stderr()).not.toContain('ktx ingest requires llm.provider.backend');
expect(io.stdout()).toBe('');
});

4
packages/cli/src/ingest.ts
View file

@ -222,7 +222,7 @@ function writeMetabaseFanoutStatus(result: LocalMetabaseFanoutResult, io: KtxIng
},
{ wikiCount: 0, slCount: 0 },
);
io.stdout.write(`Metabase fan-out: ${result.status}\n`);
io.stdout.write(`Metabase fanout: ${result.status}\n`);
io.stdout.write(`Source: ${result.metabaseConnectionId}\n`);
io.stdout.write(`Children: ${result.children.length}\n`);
if (result.totals) {
@ -719,7 +719,7 @@ export async function runKtxIngest(
localIngestOptions.queryExecutor ??
(deps.createQueryExecutor ?? createKtxCliIngestQueryExecutor)(ingestProject);
if (args.adapter === 'metabase' && args.sourceDir) {
throw new Error('source-dir uploads are not supported for the Metabase fan-out adapter');
throw new Error('source-dir uploads are not supported for the Metabase fanout adapter');
}
if (args.adapter === 'metabase') {
const executeMetabaseFanout = deps.runLocalMetabaseIngest ?? runLocalMetabaseIngest;

4
packages/cli/src/skills/sl/SKILL.md
View file

@ -124,7 +124,7 @@ Every standalone column requires `name` and `type`. Overlays have computed colum
### Grain
`grain: [col_a, col_b]` - the set of columns that uniquely identify one row. The query engine uses grain to prevent fan-out in joins. Overlays inherit grain from the manifest unless they override.
`grain: [col_a, col_b]` - the set of columns that uniquely identify one row. The query engine uses grain to prevent fanout in joins. Overlays inherit grain from the manifest unless they override.
### Joins
@ -177,7 +177,7 @@ The reverse edge (wiki pages that cite this source) is derived automatically fro
## Part 2 - Querying via `sl_query`
The `sl_query` tool generates correct SQL from a structured query. It handles joins, fan-out prevention, aggregation correctness, and filter classification automatically. Prefer it over writing raw SQL whenever the SL has the relevant sources.
The `sl_query` tool generates correct SQL from a structured query. It handles joins, fanout prevention, aggregation correctness, and filter classification automatically. Prefer it over writing raw SQL whenever the SL has the relevant sources.
### When to prefer sl_query over raw SQL

2
python/ktx-sl/AGENTS.md
View file

@ -59,7 +59,7 @@ uv run python -m semantic_layer.cli --model /tmp/model.yaml \
-q '{"measures":["orders.revenue"],"dimensions":["customers.segment"]}' --suggest
```
### 3. Test fan-out / chasm traps
### 3. Test fanout / chasm traps
Add multiple measure sources that fan out from a shared dimension hub:

2
python/ktx-sl/semantic_layer/cli.py
View file

@ -160,7 +160,7 @@ def print_plan(plan) -> None:
print(" Joins:")
for jp in plan.join_paths:
print(f" {jp}")
print(f" Fan-out: {plan.fan_out_description}")
print(f" Fanout: {plan.fan_out_description}")
if plan.aggregate_locality:
print(" Locality:")
for al in plan.aggregate_locality:

4
python/ktx-sl/semantic_layer/generator.py
View file

@ -92,7 +92,7 @@ class SqlGenerator:
return "WITH " + source_header + ",\n" + rest
return "WITH " + source_header + "\n" + outer_transpiled
# ── Path A: Simple (no fan-out) ────────────────────────────────────
# ── Path A: Simple (no fanout) ────────────────────────────────────
def _generate_simple(
self, plan: ResolvedPlan, sources: dict[str, SourceDefinition]
@ -216,7 +216,7 @@ class SqlGenerator:
shared_dim_aliases = shared_dim_aliases or set()
shared_dims = [dk for dk in all_dim_keys if dk["alias"] in shared_dim_aliases]
# Validate grain consistency: asymmetric dims cause FULL JOIN fan-out
# Validate grain consistency: asymmetric dims cause FULL JOIN fanout
if len(plan.measure_groups) > 1:
for group in plan.measure_groups:
cte_dim_aliases = {

22
python/ktx-sl/semantic_layer/planner.py
View file

@ -107,7 +107,7 @@ class QueryPlanner:
for e in tree.edges
]
# 8. Detect fan-out / chasm trap
# 8. Detect fanout / chasm trap
has_fan_out, measure_groups, fan_out_desc, locality_descs = (
self._detect_fan_out(measures, dimensions, tree, filters=query.filters)
)
@ -937,7 +937,7 @@ class QueryPlanner:
filters: list[str] | None = None,
) -> tuple[bool, list[MeasureGroup], str, list[str]]:
"""
Detect fan-out and chasm traps. Group measures by source.
Detect fanout and chasm traps. Group measures by source.
If multiple measure sources exist, each needs its own pre-aggregation CTE.
Also checks filter sources — a filter forcing a one_to_many join from the
measure source is an error (cannot be safely pre-aggregated).
@ -991,7 +991,7 @@ class QueryPlanner:
if len(groups) <= 1:
# Single measure group: check the path FROM measure source TO dimension sources.
# Only flag fan-out if those specific paths have one_to_many edges.
# Only flag fanout if those specific paths have one_to_many edges.
if groups:
source_name = next(iter(groups))
source_actual = self.graph.alias_map.get(source_name, source_name)
@ -999,7 +999,7 @@ class QueryPlanner:
for dim_src in dim_sources:
if dim_src == source_name:
continue
# Skip alias siblings (same underlying source — no fan-out)
# Skip alias siblings (same underlying source — no fanout)
dim_actual = self.graph.alias_map.get(dim_src, dim_src)
if dim_actual == source_actual:
continue
@ -1008,7 +1008,7 @@ class QueryPlanner:
has_o2m = True
break
# Also check filter sources for one_to_many fan-out
# Also check filter sources for one_to_many fanout
if not has_o2m:
for filter_src in filter_sources - dim_sources - {source_name}:
filter_actual = self.graph.alias_map.get(filter_src, filter_src)
@ -1019,7 +1019,7 @@ class QueryPlanner:
raise ValueError(
f"Filter on '{filter_src}' requires a one_to_many join "
f"from measure source '{source_name}', which would cause "
f"incorrect aggregation (fan-out). Consider rewriting the "
f"incorrect aggregation (fanout). Consider rewriting the "
f"filter as a subquery or adding the filter source as a "
f"dimension source."
)
@ -1033,10 +1033,10 @@ class QueryPlanner:
return (
True,
measure_groups,
f"Fan-out detected: one_to_many edges from {source_name} to dimensions",
f"Fanout detected: one_to_many edges from {source_name} to dimensions",
[f"Pre-aggregate {source_name} measures before joining"],
)
return False, [], "No fan-out", []
return False, [], "No fanout", []
# Multiple measure sources. Only merge groups that are provably row-safe
# (alias siblings or pure one_to_one chains). many_to_one chains are not
@ -1048,7 +1048,7 @@ class QueryPlanner:
# All measure sources are on the same safe join chain
if merged_groups:
mg_name, mg_measures = next(iter(merged_groups.items()))
# Still check if there's fan-out to dimension sources
# Still check if there's fanout to dimension sources
has_o2m = False
for dim_src in dim_sources:
if dim_src == mg_name:
@ -1061,10 +1061,10 @@ class QueryPlanner:
return (
True,
[MeasureGroup(source_name=mg_name, measures=mg_measures)],
f"Fan-out detected: one_to_many edges from {mg_name} to dimensions",
f"Fanout detected: one_to_many edges from {mg_name} to dimensions",
[f"Pre-aggregate {mg_name} measures before joining"],
)
return False, [], "No fan-out", []
return False, [], "No fanout", []
# True chasm trap — independent measure sources that can't be safely merged.
# Before building groups, validate that all filter sources are reachable

8
python/ktx-sl/tests/test_aggregate_locality.py
View file

@ -1,4 +1,4 @@
"""Dedicated tests for aggregate locality (fan-out/chasm trap correctness)."""
"""Dedicated tests for aggregate locality (fanout/chasm trap correctness)."""
import pytest
import sqlglot
@ -213,7 +213,7 @@ class TestNoFanOut:
sqlglot.parse(sql)
def test_m2o_join_no_ctes(self, ecommerce_sources):
"""orders → customers is m2o, no fan-out."""
"""orders → customers is m2o, no fanout."""
graph = JoinGraph(ecommerce_sources)
graph.build()
planner = QueryPlanner(ecommerce_sources, graph)
@ -540,7 +540,7 @@ class TestFactSideDimensionsInChasm:
"""LIMIT 1: Fact-side dimensions in chasm trap (local to one CTE only)."""
def test_fact_side_dimension_in_chasm_raises_error(self):
"""Asymmetric dim from fact_a only → raises error (would cause FULL JOIN fan-out)."""
"""Asymmetric dim from fact_a only → raises error (would cause FULL JOIN fanout)."""
hub = SourceDefinition(
name="hub",
table="public.hub",
@ -977,7 +977,7 @@ class TestBug13_FalseChasm_AliasAggregate:
dimensions=["billing_customer.name", "shipping_customer.name"],
)
plan = planner.plan(query)
assert not plan.has_fan_out, "Should not detect fan-out between alias siblings"
assert not plan.has_fan_out, "Should not detect fanout between alias siblings"
sql = gen.generate(plan, sources)
sqlglot.parse(sql)

4
python/ktx-sl/tests/test_coverage_gaps.py
View file

@ -305,12 +305,12 @@ class TestPredefinedMeasureDeps:
assert "GROUP BY" in sql.upper()
# ── Planner: fan-out with one_to_many to dimension sources (lines 595-643) ──
# ── Planner: fanout with one_to_many to dimension sources (lines 595-643) ──
class TestFanOutEdgeCases:
def test_single_source_fan_out_to_dimension(self):
"""Measure source with one_to_many to dimension should trigger fan-out."""
"""Measure source with one_to_many to dimension should trigger fanout."""
hub = SourceDefinition(
name="hub",
table="public.hub",

4
python/ktx-sl/tests/test_generator.py
View file

@ -89,10 +89,10 @@ class TestCrossSourceM2O:
class TestFanOut:
"""Test 3: Fan-out (aggregate locality)."""
"""Test 3: Fanout (aggregate locality)."""
def test_orders_by_region_no_fanout(self, planner, generator, ecommerce_sources):
"""orders → customers → regions is all m2o. No fan-out needed."""
"""orders → customers → regions is all m2o. No fanout needed."""
sql = generate_sql(
planner,
generator,

10
python/ktx-sl/tests/test_planner.py
View file

@ -200,12 +200,12 @@ class TestFanOutDetection:
class TestFanOutSingleSource:
"""Fan-out when a single measure source has o2m path to dimension source."""
"""Fanout when a single measure source has o2m path to dimension source."""
def test_reverse_path_fan_out(self):
"""Querying from customers (dimension) with measures from orders triggers fan-out
"""Querying from customers (dimension) with measures from orders triggers fanout
when the path from the measure source (orders) to the dimension source (customers)
is m2o — so no fan-out. But reversed: measure on customers, dim on orders."""
is m2o — so no fanout. But reversed: measure on customers, dim on orders."""
customers = SourceDefinition(
name="customers",
table="t",
@ -248,7 +248,7 @@ class TestFanOutSingleSource:
assert plan.has_fan_out
def test_m2o_multi_hop_no_fan_out(self, planner):
"""orders → customers → regions is all m2o. No fan-out."""
"""orders → customers → regions is all m2o. No fanout."""
query = SemanticQuery(
measures=["sum(orders.amount)"],
dimensions=["regions.name"],
@ -1116,7 +1116,7 @@ class TestDerivedMeasureEdgeCases:
assert_valid_sql(result.sql)
# ── From test_edge_cases.py: filter fan-out detection ────────────────
# ── From test_edge_cases.py: filter fanout detection ────────────────
class TestFilterFanOutDetection: