!4793 修复: prepare 结合@变量 导致的计划缓存问题

Merge pull request !4793 from chenbd/fix_mas_prepare

src/gausskernel/optimizer/commands/prepare.cpp

@@ -134,6 +134,60 @@ void TryMotJitCodegenQuery(const char* queryString, CachedPlanSource* psrc, Quer
     }
 }
 #endif
+/*
+ * User_defined variables is a string in prepareStmt.
+ * Get selectStmt/insertStmt/updateStmt/deleteStmt/mergeStmt from user_defined variables by pg_parse_query.
+ * Then, execute SQL: PREPARE stmt AS selectStmt/insertStmt/updateStmt/deleteStmt/mergeStmt.
+ */
+static void QueryRewritePrepareStmt(Node* parsetree)
+{
+    char *sqlstr = NULL;
+    List* raw_parsetree_list = NIL;
+    PrepareStmt *stmt = (PrepareStmt *)parsetree;
+    ParseState* state = make_parsestate(NULL);
+    UserVar *uservar = (UserVar *)transformExpr(state, (Node *)stmt->query, EXPR_KIND_EXECUTE_PARAMETER);
+    free_parsestate(state);
+    Const* value = (Const *)uservar->value;
+
+    if (value->consttype != TEXTOID) {
+        ereport(ERROR,
+            (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE),
+                errmsg("userdefined variable in prepare statement must be text type.")));
+    }
+    if (value->constvalue == (Datum)0) {
+        ereport(ERROR, (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE), errmsg("Query was empty")));
+    }
+
+    sqlstr = TextDatumGetCString(value->constvalue);
+
+    raw_parsetree_list = pg_parse_query(sqlstr);
+    if (raw_parsetree_list == NIL) {
+        ereport(ERROR, (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE), errmsg("Query was empty")));
+    }
+
+    if (raw_parsetree_list->length != 1) {
+        ereport(ERROR,
+            (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE),
+                errmsg("prepare user_defined variable can contain only one SQL statement.")));
+    }
+
+    switch (nodeTag(linitial(raw_parsetree_list))) {
+        case T_SelectStmt:
+        case T_InsertStmt:
+        case T_UpdateStmt:
+        case T_DeleteStmt:
+        case T_MergeStmt:
+            stmt->query = (Node *)copyObject((Node *)linitial(raw_parsetree_list));
+            break;
+        default:
+            ereport(ERROR,
+                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+                    errmsg("the statement in prepare is not supported.")));
+            break;
+    }
+
+    return ;
+}
 
 /*
  * Implements the 'PREPARE' utility statement.
@@ -155,6 +209,9 @@ void PrepareQuery(PrepareStmt* stmt, const char* queryString)
         ereport(ERROR,
             (errcode(ERRCODE_INVALID_PSTATEMENT_DEFINITION), errmsg("invalid statement name: must not be empty")));
 
+    if (IsA(stmt->query, UserVar)) {
+        QueryRewritePrepareStmt((Node*)stmt);
+    }
     /*
      * Create the CachedPlanSource before we do parse analysis, since it needs
      * to see the unmodified raw parse tree.

src/gausskernel/optimizer/rewrite/rewriteHandler.cpp

@@ -5156,62 +5156,6 @@ List* QueryRewriteCTAS(Query* parsetree)
     }
 }
 
-/*
- * User_defined variables is a string in prepareStmt.
- * Get selectStmt/insertStmt/updateStmt/deleteStmt/mergeStmt from user_defined variables by pg_parse_query.
- * Then, execute SQL: PREPARE stmt AS selectStmt/insertStmt/updateStmt/deleteStmt/mergeStmt.
- */
-List* QueryRewritePrepareStmt(Query* parsetree)
-{
-    char *sqlstr = NULL;
-    List* raw_parsetree_list = NIL;
-    List* querytree_list = NULL;
-
-    PrepareStmt *stmt = (PrepareStmt *)parsetree->utilityStmt;
-    UserVar *uservar = (UserVar *)stmt->query;
-    Const* value = (Const *)uservar->value;
-
-    if (value->consttype != TEXTOID) {
-        ereport(ERROR,
-            (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE),
-                errmsg("userdefined variable in prepare statement must be text type.")));
-    }
-    if (value->constvalue == (Datum)0) {
-        ereport(ERROR, (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE), errmsg("Query was empty")));
-    }
-
-    sqlstr = TextDatumGetCString(value->constvalue);
-
-    raw_parsetree_list = pg_parse_query(sqlstr);
-    if (raw_parsetree_list == NIL) {
-        ereport(ERROR, (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE), errmsg("Query was empty")));
-    }
-
-    if (raw_parsetree_list->length != 1) {
-        ereport(ERROR,
-            (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE),
-                errmsg("prepare user_defined variable can contain only one SQL statement.")));
-    }
-
-    switch (nodeTag(linitial(raw_parsetree_list))) {
-        case T_SelectStmt:
-        case T_InsertStmt:
-        case T_UpdateStmt:
-        case T_DeleteStmt:
-        case T_MergeStmt:
-            stmt->query = (Node *)copyObject((Node *)linitial(raw_parsetree_list));
-            break;
-        default:
-            ereport(ERROR,
-                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-                    errmsg("the statement in prepare is not supported.")));
-            break;
-    }
-
-    querytree_list = pg_analyze_and_rewrite((Node*)stmt, sqlstr, NULL, 0);
-    return querytree_list;
-}
-
 /*
  * Get value from a subquery or non-constant expression by constructing SQL.
  * input:

src/gausskernel/process/tcop/postgres.cpp

@@ -1276,9 +1276,7 @@ static List* pg_rewrite_query(Query* query)
             }
         } else if (IsA(query->utilityStmt, PrepareStmt)) {
             PrepareStmt *stmt = (PrepareStmt *)query->utilityStmt;
-            if (IsA(stmt->query, UserVar)) {
-                querytree_list = QueryRewritePrepareStmt(query);
-            } else if (IsA(stmt->query, Const)) {
+            if (IsA(stmt->query, Const)) {
                 if (((Const *)stmt->query)->constisnull) {
                     ereport(ERROR, (errcode(ERRCODE_UNRECOGNIZED_NODE_TYPE),
                             errmsg("userdefined variable in prepare statement must be text type.")));

src/include/rewrite/rewriteHandler.h

@@ -33,7 +33,6 @@ extern bool view_has_instead_trigger(Relation view, CmdType event);
 extern List* QueryRewriteCTAS(Query* parsetree);
 extern List* QueryRewriteRefresh(Query *parsetree);
 #endif
-extern List* QueryRewritePrepareStmt(Query *parsetree);
 extern Node* QueryRewriteNonConstant(Node *node);
 extern List* QueryRewriteSelectIntoVarList(Node *node, int res_len);
 extern Const* processResToConst(char* value, Oid atttypid, Oid collid);

src/test/regress/expected/mysql_compatibility.out

@@ -842,6 +842,45 @@ begin
 perform @plg := @plg + 1 from t_plg;
 end;
 $$;
+-- bugfix for in plpgsql
+prepare stmtabv as select 123;
+CREATE OR REPLACE PROCEDURE pppabc (id text) as 
+begin
+ set @abcttt = concat('select ' , id );
+ DEALLOCATE prepare stmtabv;
+ prepare stmtabv as @abcttt;
+end;
+/
+execute stmtabv;
+ ?column? 
+----------
+      123
+(1 row)
+
+call pppabc(12334);
+ pppabc 
+--------
+ 
+(1 row)
+
+execute stmtabv;
+ ?column? 
+----------
+    12334
+(1 row)
+
+call pppabc(123345);
+ pppabc 
+--------
+ 
+(1 row)
+
+execute stmtabv;
+ ?column? 
+----------
+   123345
+(1 row)
+
 --test in where 
 CREATE TABLE employee (
    id int ,

src/test/regress/sql/mysql_compatibility.sql

@@ -250,6 +250,25 @@ begin
 perform @plg := @plg + 1 from t_plg;
 end;
 $$;
+-- bugfix for in plpgsql
+prepare stmtabv as select 123;
+CREATE OR REPLACE PROCEDURE pppabc (id text) as 
+begin
+ set @abcttt = concat('select ' , id );
+ DEALLOCATE prepare stmtabv;
+ prepare stmtabv as @abcttt;
+end;
+/
+
+execute stmtabv;
+
+call pppabc(12334);
+
+execute stmtabv;
+
+call pppabc(123345);
+
+execute stmtabv;
 
 --test in where 
 CREATE TABLE employee (