diff --git a/Cargo.lock b/Cargo.lock
index 03f1b281a4c98..03cf75c3e6b2d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -6784,9 +6784,9 @@ checksum = "6bdef32e8150c2a081110b42772ffe7d7c9032b606bc226c8260fd97e0976601"
 
 [[package]]
 name = "symbolic-common"
-version = "10.1.2"
+version = "10.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "492875918a6bcbae753a5fc6f39bc87566fc3c25182e76d7f128ef1c8a2375c6"
+checksum = "56de97fb15cc5db0100c22aed51cee31b013234bc43e00e4035cad048a4c7cd8"
 dependencies = [
  "debugid",
  "memmap2",
@@ -6796,9 +6796,9 @@ dependencies = [
 
 [[package]]
 name = "symbolic-demangle"
-version = "10.1.2"
+version = "10.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "214d3a420108471222e55268ef502ba0fc89cfd4de876ff26105c560729127af"
+checksum = "0fe238e66ada3122c2efe810ba17459df9f7573b45dd523a8057e4c0f515e860"
 dependencies = [
  "cpp_demangle",
  "rustc-demangle",
@@ -7059,9 +7059,9 @@ checksum = "cda74da7e1a664f795bb1f8a87ec406fb89a02522cf6e50620d016add6dbbf5c"
 
 [[package]]
 name = "tokio"
-version = "1.21.2"
+version = "1.22.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a9e03c497dc955702ba729190dc4aac6f2a0ce97f913e5b1b5912fc5039d9099"
+checksum = "d76ce4a75fb488c605c54bf610f221cea8b0dafb53333c1a67e8ee199dcd2ae3"
 dependencies = [
  "autocfg",
  "bytes",
diff --git a/src/tests/sqlsmith/src/expr.rs b/src/tests/sqlsmith/src/expr.rs
index a5b439d3ac4af..6b3263a781deb 100644
--- a/src/tests/sqlsmith/src/expr.rs
+++ b/src/tests/sqlsmith/src/expr.rs
@@ -84,7 +84,8 @@ impl<'a, R: Rng> SqlGenerator<'a, R> {
         let range = if can_agg & !inside_agg { 99 } else { 90 };
 
         match self.rng.gen_range(0..=range) {
-            0..=80 => self.gen_func(typ, can_agg, inside_agg),
+            0..=70 => self.gen_func(typ, can_agg, inside_agg),
+            71..=80 => self.gen_exists(typ, inside_agg),
             81..=90 => self.gen_cast(typ, can_agg, inside_agg),
             91..=99 => self.gen_agg(typ),
             // TODO: There are more that are not in the functions table, e.g. CAST.
@@ -242,6 +243,22 @@ impl<'a, R: Rng> SqlGenerator<'a, R> {
             .unwrap_or_else(|| self.gen_simple_scalar(ret))
     }
 
+    fn gen_exists(&mut self, ret: DataTypeName, inside_agg: bool) -> Expr {
+        // TODO: Streaming nested loop join is not implemented yet.
+        // Tracked by: <https://github.com/singularity-data/risingwave/issues/2655>.
+
+        // Generation of subquery inside aggregation is now workaround.
+        // Tracked by: <https://github.com/risingwavelabs/risingwave/issues/3896>.
+        if self.is_mview || ret != DataTypeName::Boolean || inside_agg {
+            return self.gen_simple_scalar(ret);
+        };
+        // TODO: Feature is not yet implemented: correlated subquery in HAVING or SELECT with agg
+        // let (subquery, _) = self.gen_correlated_query();
+        // Tracked by: <https://github.com/risingwavelabs/risingwave/issues/2275>
+        let (subquery, _) = self.gen_local_query();
+        Expr::Exists(Box::new(subquery))
+    }
+
     fn gen_agg(&mut self, ret: DataTypeName) -> Expr {
         // TODO: workaround for <https://github.com/risingwavelabs/risingwave/issues/4508>
         if ret == DataTypeName::Interval {
diff --git a/src/tests/sqlsmith/src/lib.rs b/src/tests/sqlsmith/src/lib.rs
index 856c85b913651..b522e61106636 100644
--- a/src/tests/sqlsmith/src/lib.rs
+++ b/src/tests/sqlsmith/src/lib.rs
@@ -210,7 +210,7 @@ impl<'a, R: Rng> SqlGenerator<'a, R> {
     }
 
     /// Generates a query with local context.
-    /// Used by `WITH`, subquery
+    /// Used by `WITH`, `Table Subquery` in Relation
     fn gen_local_query(&mut self) -> (Query, Vec<Column>) {
         let old_ctxt = self.new_local_context();
         let t = self.gen_query();
@@ -218,6 +218,16 @@ impl<'a, R: Rng> SqlGenerator<'a, R> {
         t
     }
 
+    /// Generates a query with correlated context to ensure proper recursion.
+    /// Used by Exists `Subquery`
+    /// TODO: <https://github.com/risingwavelabs/risingwave/pull/4431#issuecomment-1327417328>
+    fn _gen_correlated_query(&mut self) -> (Query, Vec<Column>) {
+        let old_ctxt = self._clone_local_context();
+        let t = self.gen_query();
+        self.restore_context(old_ctxt);
+        t
+    }
+
     fn gen_with(&mut self) -> (Option<With>, Vec<Table>) {
         match self.flip_coin() {
             true => (None, vec![]),
diff --git a/src/tests/sqlsmith/src/utils.rs b/src/tests/sqlsmith/src/utils.rs
index 88c9084566331..fbdbc1832f68a 100644
--- a/src/tests/sqlsmith/src/utils.rs
+++ b/src/tests/sqlsmith/src/utils.rs
@@ -36,6 +36,13 @@ impl<'a, R: Rng> SqlGenerator<'a, R> {
         self.bound_relations = old_rels;
         self.bound_columns = old_cols;
     }
+
+    // TODO: <https://github.com/risingwavelabs/risingwave/pull/4431#issuecomment-1327417328>
+    pub(crate) fn _clone_local_context(&mut self) -> Context {
+        let current_bound_relations = self.bound_relations.clone();
+        let current_bound_columns = self.bound_columns.clone();
+        (current_bound_columns, current_bound_relations)
+    }
 }
 
 /// Gen utils