diff --git a/CN/modules/ROOT/nav.adoc b/CN/modules/ROOT/nav.adoc
index d0f8612..e39d870 100644
--- a/CN/modules/ROOT/nav.adoc
+++ b/CN/modules/ROOT/nav.adoc
@@ -27,6 +27,7 @@
 **** xref:master/6.3.4.adoc[%TYPE、%ROWTYPE]
 **** xref:master/6.3.5.adoc[NLS 参数]
 **** xref:master/6.3.6.adoc[函数与存储过程]
+**** xref:master/6.3.7.adoc[嵌套子函数]
 *** xref:master/6.4.adoc[国标GB18030]
 ** Oracle兼容功能列表
 *** xref:master/7.1.adoc[1、框架设计]
@@ -46,6 +47,7 @@
 *** xref:master/7.15.adoc[15、OUT 参数]
 *** xref:master/7.16.adoc[16、%TYPE、%ROWTYPE]
 *** xref:master/7.17.adoc[17、NLS 参数]
+*** xref:master/7.19.adoc[19、嵌套子函数]
 ** IvorySQL贡献指南
 *** xref:master/8.1.adoc[社区贡献指南]
 *** xref:master/8.2.adoc[asciidoc语法快速参考]
diff --git a/CN/modules/ROOT/pages/master/6.3.7.adoc b/CN/modules/ROOT/pages/master/6.3.7.adoc
new file mode 100644
index 0000000..6328405
--- /dev/null
+++ b/CN/modules/ROOT/pages/master/6.3.7.adoc
@@ -0,0 +1,113 @@
+:sectnums:
+:sectnumlevels: 5
+
+:imagesdir: ./_images
+
+= 嵌套子函数
+
+== 目的
+
+- 嵌套子函数：定义在函数、存储过程或匿名块内部的函数或存储过程，也称为 subproc 或 inner 函数。
+- 父函数：承载嵌套函数的外层函数、存储过程或匿名块，执行过程中负责实际触发子函数调用。
+
+== 实现说明
+
+=== 嵌套子函数语法识别
+
+==== 识别嵌套写法
+
+当 `DECLARE` 块里出现 `function ... is/as begin ... end` 结构时，`pl_gram.y` 会调用 `plisql_build_subproc_function()`（对应创建普通函数，这一阶段相当于在 `pg_proc` 中更新 catalog 中的注册信息）：
+
+. 在 `PLiSQL_function` 的 `subprocfuncs[]` 数组中创建 `PLiSQL_subproc_function` 结构，记录名称、参数、返回类型、属性等，获得一个下标 `fno` 作为该子函数的标识。
+. 调用 `plisql_check_subprocfunc_properties()` 校验声明与定义的合法组合。
+
+==== 数据项保存
+
+保存到父函数的 `datum` 表：编译期的 `PLiSQL_function->datums` 描述子函数里的变量、记录字段，`PLiSQL_execstate->datums` 保存着执行过程中的变量。
+
+==== 保存多态函数模板
+
+如果子函数里使用了多态参数，在语法阶段保存到 `subprocfunc->src`，同时将 `has_poly_argument` 设成 `true`，执行时按不同实参类型重新编译。
+
+=== 父函数重新编译
+
+. 父函数的 `PLiSQL_function` 结构多了一个 `subprocfuncs` 数组，里面每个元素就是刚才创建的 `PLiSQL_subproc_function`。
+. 子函数结构体 `PLiSQL_subproc_function` 有一个哈希表指针 `HTAB *poly_tab`，默认为空。当子函数里使用了多态函数时，`has_poly_argument` 为 `true`，则会在初次编译时初始化 `poly_tab`。`poly_tab` 的 key 是 `PLiSQL_func_hashkey`，记录着子函数的 `fno`、输入参数类型等； value 是编译好的 `PLiSQL_function *`（`plisql` 函数的执行上下文）。
+
+=== 调用时解析
+
+. 编译过程中，`pg` 解析器会生成一个 `ParseState` 结构，`plisql_subprocfunc_ref()` 会通过 `ParseState->p_subprocfunc_hook()` 找到父函数的 `PLiSQL_function`，调用 `plisql_ns_lookup()` 找到所有同名子函数的 `fno`，根据参数个数、类型找到最合适的多态函数。
+. `FuncExpr` 结构构造时会对子函数进行标记，方便后期执行阶段识别：`function_from = FUNC_FROM_SUBPROCFUNC`，`parent_func` 指向父级 `PLiSQL_function`，`funcid = fno`。
+. `plisql_call_handler()` 当 `function_from == FUNC_FROM_SUBPROCFUNC`，会用 `parent_func + fno` 找到对应的 `PLiSQL_subproc_function`：
+.. 如果不是多态：直接复用 `subprocfunc->function` 里的动作树。
+.. 如果是多态：先在 `poly_tab` 查有没有编译结果；没有就调用 `plisql_dynamic_compile_subproc()` 编译，放进 `poly_tab` 缓存。
+. 子函数开始执行之前，`plisql_init_subprocfunc_globalvar()` 会把父函数的 `datum` 表中有关的变量 fork 一份，这样子函数可以获取到父函数的变量值，也不会污染父函数的变量空间；执行后由 `plisql_assign_out_subprocfunc_globalvar()` 把需要回写的变量更新到父函数的 `datum` 表。
+
+== 模块设计
+
+=== PL/iSQL 语法扩展
+
+- `pl_gram.y` 新增子过程声明、嵌套定义的产生式，并在创建过程中记录 `lastoutvardno`、子过程信息等元数据。
+- 支持在子函数内引用父过程变量、子过程以及自定义类型。
+
+当 DECLARE 块内出现 `function ... is/as begin ... end` 结构时，`pl_gram.y` 会调用 `plisql_build_subproc_function()` 进行编译：
+
+. 在 `PLiSQL_function` 的 `subprocfuncs[]` 中创建 `PLiSQL_subproc_function` 结构，记录名称、参数、返回类型和属性，分配下标 `fno` 作为子函数标识。
+. 调用 `plisql_check_subprocfunc_properties()` 校验声明与定义属性组合是否合法，防止重复或缺失声明造成的语义错误。
+
+=== 数据项保存
+
+父函数的 Datum 表在编译期和执行期分别缓存子函数能访问的变量：
+
+. `PLiSQL_function->datums` 保存子函数编译阶段可见的变量与记录字段信息。
+. `PLiSQL_execstate->datums` 在执行阶段持有实时的变量数值，实现运行期访问。
+
+=== 多态函数模板
+
+若子函数包含多态参数，语法阶段会：
+
+. 将子函数源文本拷贝到 `subprocfunc->src`。
+. 设置 `has_poly_argument = true`，为后续按实参类型动态编译做好准备。
+
+=== 父函数重新编译
+
+- 父函数的 `PLiSQL_function` 结构新增 `subprocfuncs` 数组，每个元素对应一个 `PLiSQL_subproc_function`。
+- `PLiSQL_subproc_function` 持有 `HTAB *poly_tab` 指针；当 `has_poly_argument` 为 `true` 时，在首次编译时初始化该缓存，键为 `PLiSQL_func_hashkey`（子函数 `fno` + 实参类型），值为编译后的 `PLiSQL_function`。
+
+=== 解析器钩子
+
+编译期间 PostgreSQL 解析器会构造 `ParseState`，`plisql_subprocfunc_ref()` 通过 `ParseState->p_subprocfunc_hook()` 连接父函数，调用 `plisql_ns_lookup()` 找到同名子函数的全部 `fno`，并依据参数个数与类型挑选最佳候选，实现重载分发。
+
+=== FuncExpr 标记
+
+构造 `FuncExpr` 时会标记嵌套调用信息，便于执行阶段识别：
+
+- `function_from = FUNC_FROM_SUBPROCFUNC`。
+- `parent_func` 指向父级 `PLiSQL_function`。
+- `funcid = fno`，用于快速定位子函数定义。
+
+=== 嵌套函数查找机制
+
+- `plisql_subprocfunc_ref()` 作为 `ParseState->p_subprocfunc_hook` 实现入口，复用名称空间查询逻辑。
+- `plisql_get_subprocfunc_detail()` 依据参数数量、类型与命名匹配规则挑选最优候选，是嵌套函数重载的关键。
+
+=== 执行路径
+
+. `plisql_call_handler()` 判断 `function_from` 后，通过 `parent_func + fno` 找到目标 `PLiSQL_subproc_function`。
+. 对普通子函数，直接复用 `subprocfunc->function` 缓存；
+. 对多态子函数，先查询 `poly_tab`，未命中时调用 `plisql_dynamic_compile_subproc()` 动态编译并写入缓存。
+
+=== 变量同步
+
+- `plisql_init_subprocfunc_globalvar()` 在子函数执行前拷贝父函数 Datum 表中的相关变量，保证子函数读取到外层最新状态。
+- `plisql_assign_out_subprocfunc_globalvar()` 在返回前回写 OUT/INOUT 变量，确保父子函数数据一致性且互不污染。
+
+=== PSQL 端语句发送
+
+- `psqlscan.l` 调整 `proc_func_define_level` 和 `begin_depth` 的入栈/出栈逻辑，确保嵌套函数体整体发送至 SQL 端。
+- 只有当嵌套层级回到 0 且遇到分号时，才触发发送，避免子函数块被拆分。
+
+=== SQL 层返回值获取
+
+- 普通函数通过 `funcid` 访问 `pg_proc`；嵌套函数依赖 `FuncExpr.parent_func` 承载的 `PLiSQL_function`。
+- 为此实现一组函数指针（`plisql_register_internal_func()` 注册）供 SQL 层回调，按需获取嵌套函数名称、返回类型与 OUT 参数信息。
diff --git a/CN/modules/ROOT/pages/master/7.19.adoc b/CN/modules/ROOT/pages/master/7.19.adoc
new file mode 100644
index 0000000..b35a578
--- /dev/null
+++ b/CN/modules/ROOT/pages/master/7.19.adoc
@@ -0,0 +1,83 @@
+:sectnums:
+:sectnumlevels: 5
+
+:imagesdir: ./_images
+
+= 兼容Oracle 嵌套子函数
+
+== 目的
+
+- 在 IvorySQL 中使用 Oracle 风格嵌套子函数。
+
+== 功能说明
+
+- 支持在匿名块、函数或过程内部声明与调用子函数/子过程，作用域限定在父块内。
+- 子函数可读取及更新父级变量，也可定义自身局部变量；父级无法直接访问子函数内部状态。
+- 支持重载解析机制，按参数个数、类型或命名区分同名子程序。
+
+== 测试用例
+
+[source,sql]
+----
+DO $$
+DECLARE
+  v_result integer;
+  FUNCTION inner_square(p_value integer) RETURN integer IS
+  BEGIN
+    RAISE NOTICE 'inner_square called';
+    RETURN p_value * p_value;
+  END;
+BEGIN
+  v_result := inner_square(10);
+  RAISE NOTICE 'result=%', v_result;
+END;
+$$ LANGUAGE plisql;
+----
+
+[source,sql]
+----
+DO $$
+DECLARE
+  v_base_multiplier  integer := 20;
+  v_audit_counter    integer := 0;
+  v_result integer;
+  FUNCTION inner_square(p_value integer) RETURN integer IS
+  BEGIN
+    RAISE NOTICE 'inner_square called';
+    v_audit_counter := v_audit_counter + 1;
+    RETURN v_base_multiplier * p_value;
+  END;
+BEGIN
+  v_result := inner_square(10);
+  RAISE NOTICE 'result=%', v_result;
+  RAISE NOTICE 'v_audit_counter=%', v_audit_counter;
+END;
+$$ LANGUAGE plisql;
+----
+
+[source,sql]
+----
+-- Polymorphic nested function specializing on argument type
+DO $$
+DECLARE
+  v_last_notice text := 'none';
+
+  FUNCTION describe_value(p_input anyelement) RETURN text IS
+  BEGIN
+    v_last_notice := format('polymorphic dispatch with %s', pg_typeof(p_input));
+    RETURN v_last_notice;
+  END;
+
+  FUNCTION describe_value(p_input anyarray, p_element anyelement) RETURN text IS
+  BEGIN
+    v_last_notice := format('array dispatch with %s', pg_typeof(p_input)::text);
+    RETURN v_last_notice;
+  END;
+BEGIN
+  RAISE NOTICE '%', describe_value(100);
+  RAISE NOTICE '%', describe_value('IvorySQL'::text); -- explicit cast avoids ambiguous literal
+  RAISE NOTICE '%', describe_value(ARRAY[1,2,3], NULL::int); -- extra arg guides anyarray resolution
+  RAISE NOTICE 'last notice=%', v_last_notice;
+END;
+$$ LANGUAGE plisql;
+----
diff --git a/EN/modules/ROOT/nav.adoc b/EN/modules/ROOT/nav.adoc
index b046ca0..b6cb43c 100644
--- a/EN/modules/ROOT/nav.adoc
+++ b/EN/modules/ROOT/nav.adoc
@@ -11,7 +11,7 @@
 ** xref:master/4.3.adoc[Developer]
 ** xref:master/4.4.adoc[Operation Management]
 ** xref:master/4.5.adoc[Migration]
-* IvorySQL Ecosystem 
+* IvorySQL Ecosystem
 ** xref:master/5.1.adoc[PostGIS]
 ** xref:master/5.2.adoc[pgvector]
 * IvorySQL Architecture Design
@@ -26,6 +26,7 @@
 *** xref:master/6.3.4.adoc[%Type & %Rowtype]
 *** xref:master/6.3.5.adoc[NLS Parameters]
 *** xref:master/6.3.6.adoc[Function and stored procedure]
+*** xref:master/6.3.7.adoc[Nested Subfunctions]
 ** xref:master/6.4.adoc[GB18030 Character Set]
 * List of Oracle compatible features
 ** xref:master/7.1.adoc[1、Ivorysql frame design]
@@ -45,6 +46,7 @@
 ** xref:master/7.15.adoc[15、OUT Parameter]
 ** xref:master/7.16.adoc[16、%Type & %Rowtype]
 ** xref:master/7.17.adoc[17、NLS Parameters]
+** xref:master/7.19.adoc[19、Nested Subfunctions]
 * xref:master/8.adoc[Community contribution]
 * xref:master/9.adoc[Tool Reference]
 * xref:master/10.adoc[FAQ]
diff --git a/EN/modules/ROOT/pages/master/6.3.7.adoc b/EN/modules/ROOT/pages/master/6.3.7.adoc
new file mode 100644
index 0000000..5ea1eb7
--- /dev/null
+++ b/EN/modules/ROOT/pages/master/6.3.7.adoc
@@ -0,0 +1,113 @@
+:sectnums:
+:sectnumlevels: 5
+
+:imagesdir: ./_images
+
+= Nested Subfunctions
+
+== Objective
+
+- Nested subfunctions refer to functions or procedures defined inside another function, stored procedure, or anonymous block; they are also called subprocs or inner functions.
+- Parent functions are the outer functions, stored procedures, or anonymous blocks that host nested subfunctions and are responsible for invoking them during execution.
+
+== Implementation Notes
+
+=== Syntax Recognition for Nested Subfunctions
+
+==== Detecting Nested Definitions
+
+When a `DECLARE` block contains a `function ... is/as begin ... end` construct, `pl_gram.y` calls `plisql_build_subproc_function()` (similar to creating a regular function and updating the entry in `pg_proc`):
+
+. Create a `PLiSQL_subproc_function` entry in the parent `PLiSQL_function`'s `subprocfuncs[]` array to store the name, arguments, return type, and other attributes, and record the index `fno` as the identifier of this subfunction.
+. Call `plisql_check_subprocfunc_properties()` to validate the combination of declaration and definition attributes.
+
+==== Storing Datum Entries
+
+Nested subfunctions share the parent's datum table. During compilation, `PLiSQL_function->datums` describes variables and record fields inside the subfunction, while `PLiSQL_execstate->datums` keeps the runtime values.
+
+==== Preserving Polymorphic Templates
+
+If the subfunction uses polymorphic parameters, the parser stores its source code in `subprocfunc->src` and sets `has_poly_argument` to `true` so that the executor can recompile it for each distinct argument type.
+
+=== Recompiling the Parent Program
+
+. The parent `PLiSQL_function` gains a `subprocfuncs` array, each element being the `PLiSQL_subproc_function` created earlier.
+. Each `PLiSQL_subproc_function` has a `HTAB *poly_tab` pointer that is initialized on the first compilation when `has_poly_argument` is `true`. The hash key is `PLiSQL_func_hashkey`, which records the subfunction's `fno` and input argument types; the value is the compiled `PLiSQL_function *` execution context.
+
+=== Name Resolution During Invocation
+
+. PostgreSQL builds a `ParseState` structure during compilation. `plisql_subprocfunc_ref()` locates the parent `PLiSQL_function` through `ParseState->p_subprocfunc_hook()` and calls `plisql_ns_lookup()` to gather all `fno` values for subfunctions sharing the same name, then selects the best match based on argument count and types.
+. When `FuncExpr` nodes are created, the subfunction call is tagged for later execution: `function_from = FUNC_FROM_SUBPROCFUNC`, `parent_func` points to the parent `PLiSQL_function`, and `funcid = fno`.
+. In `plisql_call_handler()`, when `function_from == FUNC_FROM_SUBPROCFUNC`, the runtime fetches the appropriate `PLiSQL_subproc_function` via the pair `(parent_func, fno)`:
+.. For non-polymorphic subfunctions, reuse the precompiled action tree stored in `subprocfunc->function`.
+.. For polymorphic subfunctions, probe `poly_tab`; if there is no cached plan, call `plisql_dynamic_compile_subproc()` to compile one and store it in the cache.
+. Before execution, `plisql_init_subprocfunc_globalvar()` forks relevant entries from the parent's datum table so the subfunction can access the latest parent variables without polluting the parent scope. After execution, `plisql_assign_out_subprocfunc_globalvar()` writes back the necessary variables.
+
+== Module Design
+
+=== PL/iSQL Grammar Extensions
+
+- `pl_gram.y` adds productions for subprocedure declarations and nested definitions, and records metadata such as `lastoutvardno` and subprocedure descriptors.
+- Nested subfunctions can reference variables from the parent scope, other subprocedures, and user-defined types.
+
+Whenever a `function ... is/as begin ... end` construct is seen inside a `DECLARE` block, `pl_gram.y` invokes `plisql_build_subproc_function()`:
+
+. Insert a `PLiSQL_subproc_function` entry into the parent `PLiSQL_function->subprocfuncs[]`, storing the name, arguments, return type, and other attributes, and assign an index `fno`.
+. Call `plisql_check_subprocfunc_properties()` to verify that declarations and definitions are consistent and to prevent duplicate or missing declarations from introducing semantic errors.
+
+=== Datum Storage
+
+The parent program's datum tables hold the variables accessible to nested subfunctions during compilation and execution:
+
+. `PLiSQL_function->datums` preserves the variable and record metadata visible during compilation.
+. `PLiSQL_execstate->datums` carries the live values at runtime.
+
+=== Polymorphic Templates
+
+When a subfunction contains polymorphic arguments, the parser will:
+
+. Copy the subfunction source text into `subprocfunc->src`.
+. Set `has_poly_argument = true` to prepare for dynamic recompilation based on actual argument types.
+
+=== Parent Recompilation
+
+- The parent `PLiSQL_function` includes a `subprocfuncs` array, with each element corresponding to a `PLiSQL_subproc_function`.
+- Each `PLiSQL_subproc_function` maintains an optional `HTAB *poly_tab`; when `has_poly_argument` is `true`, the cache is initialized on the first compile. Keys are `PLiSQL_func_hashkey` (subfunction `fno` plus argument types), and values are the compiled `PLiSQL_function` plans.
+
+=== Parser Hooks
+
+During compilation, PostgreSQL creates a `ParseState`. `plisql_subprocfunc_ref()` plugs into `ParseState->p_subprocfunc_hook`, reusing the namespace lookup logic to gather candidates. `plisql_get_subprocfunc_detail()` then chooses the best match based on argument count, types, and named parameters, enabling overloaded dispatch.
+
+=== FuncExpr Annotation
+
+When constructing `FuncExpr` nodes, the compiler attaches metadata so the executor can recognize nested calls:
+
+- `function_from = FUNC_FROM_SUBPROCFUNC`.
+- `parent_func` references the owning `PLiSQL_function`.
+- `funcid = fno`, enabling direct lookup of the subfunction definition.
+
+=== Nested Subfunction Lookup
+
+- `plisql_subprocfunc_ref()` implements `ParseState->p_subprocfunc_hook` and reuses the namespace search to find nested subfunctions.
+- `plisql_get_subprocfunc_detail()` applies matching rules for argument count, type, and naming to pick the optimal overload.
+
+=== Execution Path
+
+. `plisql_call_handler()` checks `function_from`; if it is a nested subfunction, the handler locates `PLiSQL_subproc_function` via `(parent_func, fno)`.
+. For regular subfunctions, reuse the cached plan stored in `subprocfunc->function`.
+. For polymorphic subfunctions, consult `poly_tab`; on a miss, call `plisql_dynamic_compile_subproc()` to build and cache a specialized plan.
+
+=== Variable Synchronization
+
+- `plisql_init_subprocfunc_globalvar()` copies the relevant entries from the parent datum table before the subfunction runs to expose the latest state.
+- `plisql_assign_out_subprocfunc_globalvar()` writes back OUT/INOUT variables after execution to keep parent and child scopes consistent without mutual pollution.
+
+=== Statement Dispatch in psql
+
+- `psqlscan.l` adjusts the push/pop logic of `proc_func_define_level` and `begin_depth` so the nested subfunction body is transmitted to the SQL engine as a whole.
+- Statements are sent only when the nesting depth returns to zero and a semicolon is reached, avoiding partial dispatch of subfunction blocks.
+
+=== Retrieving Return Information on the SQL Side
+
+- Regular functions obtain metadata via `funcid` from `pg_proc`; nested subfunctions rely on `FuncExpr.parent_func`, which holds the parent `PLiSQL_function`.
+- A set of callback pointers (registered through `plisql_register_internal_func()`) allows the SQL layer to fetch nested subfunction names, return types, and OUT parameter information on demand.
diff --git a/EN/modules/ROOT/pages/master/7.19.adoc b/EN/modules/ROOT/pages/master/7.19.adoc
new file mode 100644
index 0000000..601766c
--- /dev/null
+++ b/EN/modules/ROOT/pages/master/7.19.adoc
@@ -0,0 +1,83 @@
+:sectnums:
+:sectnumlevels: 5
+
+:imagesdir: ./_images
+
+= Oracle-Compatible Nested Subfunctions
+
+== Objective
+
+- Using Oracle-style nested subfunctions in IvorySQL.
+
+== Feature Description
+
+- Allows declaring and invoking subfunctions or subprocedures inside anonymous blocks, functions, or procedures, with scope limited to the parent block.
+- Nested subfunctions can read and update variables defined in the parent scope while introducing their own local variables; the parent scope cannot directly access the subfunction's internal state.
+- Supports overloading resolution that distinguishes homonymous subfunctions by argument count, data type, or named parameters.
+
+== Test Cases
+
+[source,sql]
+----
+DO $$
+DECLARE
+  v_result integer;
+  FUNCTION inner_square(p_value integer) RETURN integer IS
+  BEGIN
+    RAISE NOTICE 'inner_square called';
+    RETURN p_value * p_value;
+  END;
+BEGIN
+  v_result := inner_square(10);
+  RAISE NOTICE 'result=%', v_result;
+END;
+$$ LANGUAGE plisql;
+----
+
+[source,sql]
+----
+DO $$
+DECLARE
+  v_base_multiplier  integer := 20;
+  v_audit_counter    integer := 0;
+  v_result integer;
+  FUNCTION inner_square(p_value integer) RETURN integer IS
+  BEGIN
+    RAISE NOTICE 'inner_square called';
+    v_audit_counter := v_audit_counter + 1;
+    RETURN v_base_multiplier * p_value;
+  END;
+BEGIN
+  v_result := inner_square(10);
+  RAISE NOTICE 'result=%', v_result;
+  RAISE NOTICE 'v_audit_counter=%', v_audit_counter;
+END;
+$$ LANGUAGE plisql;
+----
+
+[source,sql]
+----
+-- Polymorphic nested function specializing on argument type
+DO $$
+DECLARE
+  v_last_notice text := 'none';
+
+  FUNCTION describe_value(p_input anyelement) RETURN text IS
+  BEGIN
+    v_last_notice := format('polymorphic dispatch with %s', pg_typeof(p_input));
+    RETURN v_last_notice;
+  END;
+
+  FUNCTION describe_value(p_input anyarray, p_element anyelement) RETURN text IS
+  BEGIN
+    v_last_notice := format('array dispatch with %s', pg_typeof(p_input)::text);
+    RETURN v_last_notice;
+  END;
+BEGIN
+  RAISE NOTICE '%', describe_value(100);
+  RAISE NOTICE '%', describe_value('IvorySQL'::text); -- explicit cast avoids ambiguous literal
+  RAISE NOTICE '%', describe_value(ARRAY[1,2,3], NULL::int); -- extra arg guides anyarray resolution
+  RAISE NOTICE 'last notice=%', v_last_notice;
+END;
+$$ LANGUAGE plisql;
+----