From 296108c5a3a61fa4b55254dcebd4e864305c16eb Mon Sep 17 00:00:00 2001
From: wangfeihuo <wangfeihuo@huawei.com>
Date: Fri, 18 Apr 2025 10:31:32 +0800
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---
 ...02\346\225\260\350\257\264\346\230\216.md" | 46 +++++++++++++++++++
 ...02\346\225\260\350\257\264\346\230\216.md" | 46 +++++++++++++++++++
 2 files changed, 92 insertions(+)

diff --git "a/content/docs-lite/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md" "b/content/docs-lite/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md"
index 884e178e8..1b27ab458 100644
--- "a/content/docs-lite/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md"
+++ "b/content/docs-lite/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md"
@@ -1315,3 +1315,49 @@ openGauss=# select * from t_prepare_010;
 (1 row)
 
 ```
+
+
+## dolphin.transform_unknown_param_type_to_match_index_first
+
+**参数说明**：该参数打开后，对于谓词条件，如果谓词左右分别是整型索引列和未知类型的参数类型，那么优先将未知类型的参数解释成索引列的类型进行比较，从而避免因为隐式转换导致索引失效的问题。
+
+该参数目前属于USERSET类型参数，请参考[表1](dolphin-重设参数.md#zh-cn_topic_0283137176_zh-cn_topic_0237121562_zh-cn_topic_0059777490_t91a6f212010f4503b24d7943aed6d837)中对应设置方法进行设置。
+
+**取值范围**：布尔型
+
+**默认值**：false
+
+**示例**：
+
+```
+openGauss=# create table test_index(c1 int, c2 varchar);
+CREATE TABLE
+openGauss=# insert into test_index values (generate_series(1,100), generate_series(1,100));
+INSERT 0 100
+openGauss=# create index index1 on test_index(c1);
+CREATE INDEX
+openGauss=# analyze test_index;
+ANALYZE
+openGauss=# set dolphin.transform_unknown_param_type_to_match_index_first=off;
+SET
+openGauss=# prepare s1 as select * from test_index where c1 = ?;
+PREPARE
+openGauss=# explain execute s1 using 1;
+                                   QUERY PLAN
+--------------------------------------------------------------------------------
+ Seq Scan on test_index  (cost=10000000000.00..1000000000250.00 rows=1 width=6)
+   Filter: ((c1)::double precision = $1)
+(2 rows)
+
+openGauss=# set dolphin.transform_unknown_param_type_to_match_index_first=on;
+SET
+openGauss=# prepare s1 as select * from test_index where c1 = ?;
+PREPARE
+openGauss=# explain execute s1 using 1;
+                               QUERY PLAN
+-------------------------------------------------------------------------
+ [Bypass]
+ Index Scan using index1 on test_index  (cost=0.00..8.27 rows=1 width=6)
+   Index Cond: (c1 = $1)
+(3 rows)
+```
\ No newline at end of file
diff --git "a/content/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md" "b/content/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md"
index 5df5d5adb..c635d8d22 100644
--- "a/content/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md"
+++ "b/content/zh/docs/ExtensionReference/dolphin-GUC\345\217\202\346\225\260\350\257\264\346\230\216.md"
@@ -1316,4 +1316,50 @@ openGauss=# select * from t_prepare_010;
   1
 (1 row)
 
+```
+
+
+## dolphin.transform_unknown_param_type_to_match_index_first
+
+**参数说明**：该参数打开后，对于谓词条件，如果谓词左右分别是整型索引列和未知类型的参数类型，那么优先将未知类型的参数解释成索引列的类型进行比较，从而避免因为隐式转换导致索引失效的问题。
+
+该参数目前属于USERSET类型参数，请参考[表1](dolphin-重设参数.md#zh-cn_topic_0283137176_zh-cn_topic_0237121562_zh-cn_topic_0059777490_t91a6f212010f4503b24d7943aed6d837)中对应设置方法进行设置。
+
+**取值范围**：布尔型
+
+**默认值**：false
+
+**示例**：
+
+```
+openGauss=# create table test_index(c1 int, c2 varchar);
+CREATE TABLE
+openGauss=# insert into test_index values (generate_series(1,100), generate_series(1,100));
+INSERT 0 100
+openGauss=# create index index1 on test_index(c1);
+CREATE INDEX
+openGauss=# analyze test_index;
+ANALYZE
+openGauss=# set dolphin.transform_unknown_param_type_to_match_index_first=off;
+SET
+openGauss=# prepare s1 as select * from test_index where c1 = ?;
+PREPARE
+openGauss=# explain execute s1 using 1;
+                                   QUERY PLAN
+--------------------------------------------------------------------------------
+ Seq Scan on test_index  (cost=10000000000.00..1000000000250.00 rows=1 width=6)
+   Filter: ((c1)::double precision = $1)
+(2 rows)
+
+openGauss=# set dolphin.transform_unknown_param_type_to_match_index_first=on;
+SET
+openGauss=# prepare s1 as select * from test_index where c1 = ?;
+PREPARE
+openGauss=# explain execute s1 using 1;
+                               QUERY PLAN
+-------------------------------------------------------------------------
+ [Bypass]
+ Index Scan using index1 on test_index  (cost=0.00..8.27 rows=1 width=6)
+   Index Cond: (c1 = $1)
+(3 rows)
 ```
\ No newline at end of file
-- 
Gitee