diff --git a/packages/opencode/src/altimate/telemetry/index.ts b/packages/opencode/src/altimate/telemetry/index.ts
index 4ab8fa2a7..023879bfb 100644
--- a/packages/opencode/src/altimate/telemetry/index.ts
+++ b/packages/opencode/src/altimate/telemetry/index.ts
@@ -644,8 +644,14 @@ export namespace Telemetry {
         session_id: string
         /** skipped = no cache or stale, passed = valid SQL, blocked = invalid SQL caught, error = validation itself failed */
         outcome: "skipped" | "passed" | "blocked" | "error"
-        /** why: no_cache, stale_cache, empty_cache, valid, non_structural, structural_error, validation_exception */
+        /** why: no_cache, stale_cache, empty_cache, valid, non_structural, structural_error, dispatcher_failed, validation_exception */
         reason: string
+        /** warehouse driver type (postgres, snowflake, bigquery, ...) — enables per-warehouse catch-rate analysis */
+        warehouse_type: string
+        /** read / write / unknown — enables per-query-type analysis */
+        query_type: string
+        /** SHA-256 prefix of masked SQL — join key to sql_execute_failure events for same query */
+        masked_sql_hash: string
         schema_columns: number
         /** true when schema scan hit the column-scan cap — flags samples biased by large-warehouse truncation */
         schema_truncated: boolean
diff --git a/packages/opencode/src/altimate/tools/sql-execute.ts b/packages/opencode/src/altimate/tools/sql-execute.ts
index 3bcb77d21..a0588b413 100644
--- a/packages/opencode/src/altimate/tools/sql-execute.ts
+++ b/packages/opencode/src/altimate/tools/sql-execute.ts
@@ -43,7 +43,7 @@ export const SqlExecuteTool = Tool.define("sql_execute", {
     // but does NOT block execution. Used to measure catch rate before deciding
     // whether to enable blocking in a future release. Fire-and-forget so it
     // doesn't add latency to the sql_execute hot path.
-    preValidateSql(args.query, args.warehouse).catch(() => {})
+    preValidateSql(args.query, args.warehouse, queryType).catch(() => {})
     // altimate_change end
 
     try {
@@ -115,8 +115,16 @@ interface PreValidationResult {
   error?: string
 }
 
-async function preValidateSql(sql: string, warehouse?: string): Promise<PreValidationResult> {
+async function preValidateSql(sql: string, warehouse: string | undefined, queryType: string): Promise<PreValidationResult> {
   const startTime = Date.now()
+  // Yield the event loop before heavy synchronous SQLite work so concurrent
+  // tasks aren't blocked. Bun's sqlite API is sync and listColumns can touch
+  // hundreds of thousands of rows for large warehouses.
+  await new Promise<void>((resolve) => setImmediate(resolve))
+
+  // Precompute correlation fields used in every telemetry event this function emits.
+  const maskedSqlHash = Telemetry.hashError(Telemetry.maskString(sql))
+
   try {
     // Resolve the warehouse the same way sql.execute's fallback path does:
     // when caller omits `warehouse`, sql.execute uses Registry.list()[0].
@@ -124,13 +132,22 @@ async function preValidateSql(sql: string, warehouse?: string): Promise<PreValid
     // execution (dbt-routed queries are a known gap — they short-circuit
     // before this fallback, so validation may use a different warehouse
     // than the one dbt selects).
+    const registered = Registry.list().warehouses
     let warehouseName = warehouse
     if (!warehouseName) {
-      const registered = Registry.list().warehouses
       warehouseName = registered[0]?.name
     }
+    const warehouseInfo = registered.find((w) => w.name === warehouseName)
+    const warehouseType = warehouseInfo?.type ?? "unknown"
+
+    const ctx: TrackCtx = {
+      warehouse_type: warehouseType,
+      query_type: queryType,
+      masked_sql_hash: maskedSqlHash,
+    }
+
     if (!warehouseName) {
-      trackPreValidation("skipped", "no_cache", 0, Date.now() - startTime, false)
+      trackPreValidation("skipped", "no_cache", 0, Date.now() - startTime, false, ctx)
       return { blocked: false }
     }
 
@@ -139,14 +156,14 @@ async function preValidateSql(sql: string, warehouse?: string): Promise<PreValid
 
     const warehouseStatus = status.warehouses.find((w) => w.name === warehouseName)
     if (!warehouseStatus?.last_indexed) {
-      trackPreValidation("skipped", "no_cache", 0, Date.now() - startTime, false)
+      trackPreValidation("skipped", "no_cache", 0, Date.now() - startTime, false, ctx)
       return { blocked: false }
     }
 
     // Check cache freshness
     const cacheAge = Date.now() - new Date(warehouseStatus.last_indexed).getTime()
     if (cacheAge > CACHE_TTL_MS) {
-      trackPreValidation("skipped", "stale_cache", 0, Date.now() - startTime, false)
+      trackPreValidation("skipped", "stale_cache", 0, Date.now() - startTime, false, ctx)
       return { blocked: false }
     }
 
@@ -154,16 +171,24 @@ async function preValidateSql(sql: string, warehouse?: string): Promise<PreValid
     const columns = cache.listColumns(warehouseName, COLUMN_SCAN_LIMIT)
     const schemaTruncated = columns.length >= COLUMN_SCAN_LIMIT
     if (columns.length === 0) {
-      trackPreValidation("skipped", "empty_cache", 0, Date.now() - startTime, false)
+      trackPreValidation("skipped", "empty_cache", 0, Date.now() - startTime, false, ctx)
       return { blocked: false }
     }
 
-    const schemaContext: Record<string, any> = {}
+    // Build schema context keyed by fully-qualified name (database.schema.table)
+    // so multi-database warehouses don't collide on schema+table alone.
+    // Dedupe columns per table to defend against residual collisions.
+    const schemaContext: Record<string, { name: string; type: string; nullable: boolean }[]> = {}
+    const seenColumns: Record<string, Set<string>> = {}
     for (const col of columns) {
-      const tableName = col.schema_name ? `${col.schema_name}.${col.table}` : col.table
+      const tableName = [col.database, col.schema_name, col.table].filter(Boolean).join(".")
+      if (!tableName) continue
       if (!schemaContext[tableName]) {
         schemaContext[tableName] = []
+        seenColumns[tableName] = new Set()
       }
+      if (seenColumns[tableName].has(col.name)) continue
+      seenColumns[tableName].add(col.name)
       schemaContext[tableName].push({
         name: col.name,
         type: col.data_type || "VARCHAR",
@@ -178,60 +203,61 @@ async function preValidateSql(sql: string, warehouse?: string): Promise<PreValid
       schema_context: schemaContext,
     })
 
+    // If the dispatcher itself failed, don't treat missing data as "valid".
+    if (!validationResult.success) {
+      const errMsg = typeof validationResult.error === "string" ? validationResult.error : undefined
+      trackPreValidation("error", "dispatcher_failed", 0, Date.now() - startTime, false, ctx, errMsg)
+      return { blocked: false }
+    }
+
     const data = (validationResult.data ?? {}) as Record<string, any>
     const errors = Array.isArray(data.errors) ? data.errors : []
     const isValid = data.valid !== false && errors.length === 0
 
     if (isValid) {
-      trackPreValidation("passed", "valid", columns.length, Date.now() - startTime, schemaTruncated)
+      trackPreValidation("passed", "valid", columns.length, Date.now() - startTime, schemaTruncated, ctx)
       return { blocked: false }
     }
 
     // Only block on high-confidence structural errors
     const structuralErrors = errors.filter((e: any) => {
       const msg = (e.message ?? "").toLowerCase()
-      return msg.includes("column") || msg.includes("table") || msg.includes("not found") || msg.includes("does not exist")
+      return /\b(column|table|view|relation|identifier|not found|does not exist)\b/.test(msg)
     })
 
     if (structuralErrors.length === 0) {
       // Non-structural errors (ambiguous cases) — let them through
-      trackPreValidation("passed", "non_structural", columns.length, Date.now() - startTime, schemaTruncated)
+      trackPreValidation("passed", "non_structural", columns.length, Date.now() - startTime, schemaTruncated, ctx)
       return { blocked: false }
     }
 
-    // Build helpful error with available columns
     const errorMsgs = structuralErrors.map((e: any) => e.message).join("\n")
-    const referencedTables = Object.keys(schemaContext).slice(0, 10)
-    const availableColumns = referencedTables
-      .map((t) => `${t}: ${schemaContext[t].map((c: any) => c.name).join(", ")}`)
-      .join("\n")
-
-    const errorOutput = [
-      `Pre-execution validation failed (validated against cached schema):`,
-      ``,
-      errorMsgs,
-      ``,
-      `Available tables and columns:`,
-      availableColumns,
-      ``,
-      `Fix the query and retry. If the schema cache is outdated, run schema_index to refresh it.`,
-    ].join("\n")
-
-    trackPreValidation("blocked", "structural_error", columns.length, Date.now() - startTime, schemaTruncated, errorMsgs)
-    return { blocked: true, error: errorOutput }
+    trackPreValidation("blocked", "structural_error", columns.length, Date.now() - startTime, schemaTruncated, ctx, errorMsgs)
+    // Shadow mode: caller discards the result. When blocking is enabled in the
+    // future, build errorOutput here with the structural errors and
+    // schemaContext keys for user-facing guidance.
+    return { blocked: false }
   } catch {
     // Validation failure should never block execution
-    trackPreValidation("error", "validation_exception", 0, Date.now() - startTime, false)
+    const ctx: TrackCtx = { warehouse_type: "unknown", query_type: queryType, masked_sql_hash: maskedSqlHash }
+    trackPreValidation("error", "validation_exception", 0, Date.now() - startTime, false, ctx)
     return { blocked: false }
   }
 }
 
+interface TrackCtx {
+  warehouse_type: string
+  query_type: string
+  masked_sql_hash: string
+}
+
 function trackPreValidation(
   outcome: "skipped" | "passed" | "blocked" | "error",
   reason: string,
   schema_columns: number,
   duration_ms: number,
   schema_truncated: boolean,
+  ctx: TrackCtx,
   error_message?: string,
 ) {
   // Mask schema identifiers (table / column names, paths, user IDs) from the
@@ -244,6 +270,9 @@ function trackPreValidation(
     session_id: Telemetry.getContext().sessionId,
     outcome,
     reason,
+    warehouse_type: ctx.warehouse_type,
+    query_type: ctx.query_type,
+    masked_sql_hash: ctx.masked_sql_hash,
     schema_columns,
     schema_truncated,
     duration_ms,
diff --git a/packages/opencode/test/telemetry/telemetry.test.ts b/packages/opencode/test/telemetry/telemetry.test.ts
index 10aef0aa9..8500ac6c3 100644
--- a/packages/opencode/test/telemetry/telemetry.test.ts
+++ b/packages/opencode/test/telemetry/telemetry.test.ts
@@ -245,11 +245,12 @@ const ALL_EVENT_TYPES: Telemetry.Event["type"][] = [
   "sql_execute_failure",
   "feature_suggestion",
   "core_failure",
+  "sql_pre_validation",
 ]
 
 describe("telemetry.event-types", () => {
   test("all event types are valid", () => {
-    expect(ALL_EVENT_TYPES.length).toBe(42)
+    expect(ALL_EVENT_TYPES.length).toBe(43)
   })
 })