chore: auto-commit (5 archivos)

- playground/tables/CMakeLists.txt
- playground/tables/data_table.cpp
- playground/tables/self_test.cpp
- playground/tables/tql_duckdb.cpp
- playground/tables/tql_duckdb.h

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

playground/tables/self_test.cpp

@@ -11,6 +11,9 @@
 #include "lua_engine.h"
 #include "tql.h"
 #include "tql_to_sql.h"
+#ifdef FN_TQL_DUCKDB
+#  include "tql_duckdb.h"
+#endif
 
 #include <cmath>
 #include <cstdio>
@@ -2830,6 +2833,89 @@ return {
         putenv((char*)"FN_LLM_MOCK_RESPONSE=");
     }
 
+#ifdef FN_TQL_DUCKDB
+    // === phase11 round-trip TQL emit -> DuckDB execute -> match compute_stage ===
+    {
+        // Setup tabla "users" con 5 rows.
+        const char* cells[] = {
+            "go",  "10",
+            "go",  "20",
+            "py",  "30",
+            "py",  "40",
+            "cpp", "50",
+        };
+        TableInput t;
+        t.name    = "users";
+        t.headers = {"lang", "n"};
+        t.types   = {ColumnType::String, ColumnType::Int};
+        t.cells   = cells;
+        t.rows    = 5;
+        t.cols    = 2;
+        std::vector<TableInput> tables = {t};
+
+        // Caso A: stage 0 simple SELECT
+        {
+            State st;
+            st.stages.resize(1);
+            auto e = tql_to_sql::emit_sql(st, tables);
+            check(e.error.empty(), "phase11 rt: stage0 emit OK");
+            auto r = tql_duckdb::execute(e.sql, e.params, tables);
+            check(r.error.empty(), "phase11 rt: stage0 execute OK");
+            check(r.out.rows == 5, "phase11 rt: stage0 5 rows");
+            check(r.out.cols == 2, "phase11 rt: stage0 2 cols");
+        }
+
+        // Caso B: stage 1 group by lang + count
+        {
+            State st;
+            st.stages.resize(2);
+            st.stages[1].breakouts.push_back("lang");
+            st.stages[1].aggregations.push_back({AggFn::Count});
+            st.active_stage = 1;
+            auto e = tql_to_sql::emit_sql(st, tables);
+            check(e.error.empty(), "phase11 rt: group emit OK");
+            auto r = tql_duckdb::execute(e.sql, e.params, tables);
+            check(r.error.empty(), "phase11 rt: group execute OK");
+            check(r.out.rows == 3, "phase11 rt: 3 grupos (go/py/cpp)");
+            check(r.out.cols == 2, "phase11 rt: cols = lang + count");
+        }
+
+        // Caso C: filter Op::Eq
+        {
+            State st;
+            st.stages.resize(1);
+            st.stages[0].filters.push_back({0, Op::Eq, "go"});
+            auto e = tql_to_sql::emit_sql(st, tables);
+            check(e.error.empty(), "phase11 rt: filter emit OK");
+            auto r = tql_duckdb::execute(e.sql, e.params, tables);
+            check(r.error.empty(), "phase11 rt: filter execute OK");
+            check(r.out.rows == 2, "phase11 rt: filter -> 2 rows go");
+        }
+
+        // Caso D: aggregation sum
+        {
+            State st;
+            st.stages.resize(2);
+            st.stages[1].breakouts.push_back("lang");
+            st.stages[1].aggregations.push_back({AggFn::Sum, "n"});
+            st.active_stage = 1;
+            auto e = tql_to_sql::emit_sql(st, tables);
+            check(e.error.empty(), "phase11 rt: sum emit OK");
+            auto r = tql_duckdb::execute(e.sql, e.params, tables);
+            check(r.error.empty(), "phase11 rt: sum execute OK");
+            check(r.out.rows == 3, "phase11 rt: sum 3 grupos");
+            // Verifica que sum_n para "go" es 30 (10+20)
+            bool found_go_30 = false;
+            for (int rr = 0; rr < r.out.rows; ++rr) {
+                std::string lang = r.out.cells[rr * 2 + 0];
+                std::string sum  = r.out.cells[rr * 2 + 1];
+                if (lang == "go" && (sum == "30" || sum == "30.0")) found_go_30 = true;
+            }
+            check(found_go_30, "phase11 rt: sum_n(go) = 30");
+        }
+    }
+#endif
+
     std::printf("\n=== %d passed, %d failed ===\n", passed, failed);
     return failed == 0 ? 0 : 1;
 }