Do not treat interpolated expressions as identifiers

java/com/metabase/macaw/AstWalker.java

@@ -442,6 +442,10 @@ public void visit(OverlapsCondition overlapsCondition) {
 
     @Override
     public <S> T visit(Column tableColumn, S context) {
+        // Ignore nested queries. In the future, we could do a nested part of them and merge the results.
+        if (tableColumn.getColumnName().startsWith("$$")) {
+            return null;
+        }
         invokeCallback(COLUMN, tableColumn);
 
         Table table = tableColumn.getTable();

java/com/metabase/macaw/BasicTableExtractor.java

@@ -91,7 +91,7 @@ private static Set<Table> getTables(PlainSelect select) {
                 tables.add(table);
             } else if (item instanceof TableFunction) {
                 // Do not allow dynamic tables
-                throw new AnalysisError(AnalysisErrorType.INVALID_QUERY);
+                throw new AnalysisError(AnalysisErrorType.UNSUPPORTED_EXPRESSION);
             } else {
                 // Only allow simple table references.
                 throw new AnalysisError(AnalysisErrorType.UNSUPPORTED_EXPRESSION);

java/com/metabase/macaw/CompoundTableExtractor.java

@@ -125,7 +125,7 @@ private static void accTables(PlainSelect select, Set<Table> tables, Stack<Set<S
                 }
             } else if (item instanceof TableFunction) {
                 // Do not allow dynamic tables
-                throw new AnalysisError(AnalysisErrorType.INVALID_QUERY);
+                throw new AnalysisError(AnalysisErrorType.UNSUPPORTED_EXPRESSION);
             } else if (item instanceof Select) {
                 accTables((Select) item, tables, cteAliasScopes);
             } else if (item != null) {

test/macaw/acceptance_test.clj

@@ -209,5 +209,6 @@
   (test-fixture :compound/cte-nonambiguous)
   (test-fixture :literal/with-table)
   (test-fixture :literal/without-table)
+  (test-fixture :interpolation/crosstab)
 
   (test-fixture :broken/filter-where))

test/resources/acceptance/interpolation__crosstab.analysis.edn

@@ -0,0 +1,10 @@
+{:tables         [{:table "history"}]
+ :source-columns [{:table "history" :column "id"}
+                  {:table "history" :column "page"}
+                  {:table "history" :column "h_timestamp"}]
+ :overrides
+ {:ast-walker-1
+  {:tables         []
+   :source-columns []}
+  :basic-select    :macaw.error/unsupported-expression
+  :compound-select :macaw.error/unsupported-expression}}

test/resources/acceptance/interpolation__crosstab.sql

@@ -0,0 +1,20 @@
+SELECT * FROM crosstab($$
+
+    SELECT
+        history.page,
+        date_trunc('month', history.h_timestamp)::DATE,
+        count(history.id) as total
+    FROM history
+    WHERE h_timestamp between '2024-01-01' and '2024-12-01'
+    GROUP BY page, date_trunc('month', history.h_timestamp)
+$$,
+
+        $$
+            SELECT
+                date_trunc('month', generate_series('2024-01-01', '2024-02-01', '1 month'::INTERVAL))::DATE
+$$
+) AS ct(
+    page INTEGER,
+    "Jan" FLOAT,
+    "Feb" FLOAT
+)