fix: 四个 SEQUENCE 主键实体显式声明序列名并固化 allocationSize=50，兼容达梦手工预建序列

flow-engine-example/src/main/resources/application-dm.properties

@@ -6,6 +6,23 @@ spring.jpa.properties.hibernate.dialect=com.codingapi.example.dialect.HydDmDiale
 
 # 开启 JDBC 批次插入，配合 SEQUENCE 主键（t_flow_record/t_flow_todo_record/t_flow_todo_marge/t_flow_sub_process_record）
 # 将批量创建流程记录/待办/合并/子流程时的多次串行 INSERT 合并为批次往返，显著降低远程库耗时
+#
+# ⚠️ 达梦主键序列约定：
+#   这四个实体显式声明了 @SequenceGenerator，序列名固定为 t_flow_record_seq /
+#   t_flow_todo_record_seq / t_flow_todo_marge_seq / t_flow_sub_process_record_seq，
+#   allocationSize = 50。
+#   Hibernate 的 ddl-auto=update 在达梦上自动建序列并不可靠，请【首次部署前手工预建】这四个序列，
+#   且 INCREMENT BY 必须与 allocationSize(50) 严格一致（否则 pooled 优化器可能主键重复）。
+#   起始值 start with 按表是否有历史数据决定（pooled 发号从 start 起连续递增，绝不下探到 start 以下）：
+#     ⚪ 表为空：                    start with 1   increment by 50
+#     🟠 表已存在数据（id 到 N）：    start with (N+1) increment by 50  ← 务必为已占用的最大 id + 1，否则新号撞历史主键
+#   示例（空表）：
+#     create sequence t_flow_record_seq            increment by 50 start with 1;
+#     create sequence t_flow_todo_record_seq       increment by 50 start with 1;
+#     create sequence t_flow_todo_marge_seq        increment by 50 start with 1;
+#     create sequence t_flow_sub_process_record_seq increment by 50 start with 1;
+#   注意：INCREMENT BY（序列步长）与下方的 jdbc.batch_size（JDBC 批插行数）是两个独立概念，
+#   两者无需一致；真正必须一致的是 序列步长 == allocationSize。
 spring.jpa.properties.hibernate.jdbc.batch_size=100
 spring.jpa.properties.hibernate.order_inserts=true
 spring.jpa.properties.hibernate.order_updates=true

flow-engine-example/src/main/resources/sql/dm-sequences.sql

@@ -0,0 +1,74 @@
+-- =====================================================================
+-- 达梦( DM ) 主键序列预建脚本
+-- =====================================================================
+-- 适用表( SEQUENCE 主键，配合 hibernate 批插 ):
+--   t_flow_record            -> t_flow_record_seq
+--   t_flow_todo_record       -> t_flow_todo_record_seq
+--   t_flow_todo_marge        -> t_flow_todo_marge_seq
+--   t_flow_sub_process_record-> t_flow_sub_process_record_seq
+--
+-- 序列名 / 步长 与实体 @SequenceGenerator(sequenceName=..., allocationSize=50) 严格一致，
+-- 请勿修改，否则 hibernate 会在 insert 时报“无法解析的成员访问表达式[...NEXTVAL]”或出现主键重复。
+--
+-- 特性:
+--   * INCREMENT BY 固定 50（必须 == allocationSize，paired/pooled 优化器要求，否则可能主键重复）
+--   * START WITH 自动取 「表 max(id) + 1」：表为空则 1，表有历史数据则最大 id+1（绝不撞已有主键）
+--   * 幂等：序列已存在则跳过，可反复执行
+--   * 基于当前登录用户(USER)所在模式，与表和序列归属一致
+--
+-- 执行方式：DBA 工具(达梦管理工具/disql) 以应用同款账号(默认 SYSDBA) 执行本脚本即可。
+-- =====================================================================
+
+DECLARE
+    v_cnt   INT;
+    v_start BIGINT;
+BEGIN
+    -- ---------- 1. t_flow_record_seq ----------
+    SELECT COUNT(*) INTO v_cnt FROM all_sequences
+     WHERE sequence_name = 'T_FLOW_RECORD_SEQ' AND sequence_owner = USER;
+    IF v_cnt = 0 THEN
+        BEGIN
+            SELECT NVL(MAX(id), 0) + 1 INTO v_start FROM t_flow_record;
+        EXCEPTION WHEN OTHERS THEN
+            v_start := 1;   -- 表不存在或为空
+        END;
+        EXECUTE IMMEDIATE 'CREATE SEQUENCE t_flow_record_seq INCREMENT BY 50 START WITH ' || v_start;
+    END IF;
+
+    -- ---------- 2. t_flow_todo_record_seq ----------
+    SELECT COUNT(*) INTO v_cnt FROM all_sequences
+     WHERE sequence_name = 'T_FLOW_TODO_RECORD_SEQ' AND sequence_owner = USER;
+    IF v_cnt = 0 THEN
+        BEGIN
+            SELECT NVL(MAX(id), 0) + 1 INTO v_start FROM t_flow_todo_record;
+        EXCEPTION WHEN OTHERS THEN
+            v_start := 1;
+        END;
+        EXECUTE IMMEDIATE 'CREATE SEQUENCE t_flow_todo_record_seq INCREMENT BY 50 START WITH ' || v_start;
+    END IF;
+
+    -- ---------- 3. t_flow_todo_marge_seq ----------
+    SELECT COUNT(*) INTO v_cnt FROM all_sequences
+     WHERE sequence_name = 'T_FLOW_TODO_MARGE_SEQ' AND sequence_owner = USER;
+    IF v_cnt = 0 THEN
+        BEGIN
+            SELECT NVL(MAX(id), 0) + 1 INTO v_start FROM t_flow_todo_marge;
+        EXCEPTION WHEN OTHERS THEN
+            v_start := 1;
+        END;
+        EXECUTE IMMEDIATE 'CREATE SEQUENCE t_flow_todo_marge_seq INCREMENT BY 50 START WITH ' || v_start;
+    END IF;
+
+    -- ---------- 4. t_flow_sub_process_record_seq ----------
+    SELECT COUNT(*) INTO v_cnt FROM all_sequences
+     WHERE sequence_name = 'T_FLOW_SUB_PROCESS_RECORD_SEQ' AND sequence_owner = USER;
+    IF v_cnt = 0 THEN
+        BEGIN
+            SELECT NVL(MAX(id), 0) + 1 INTO v_start FROM t_flow_sub_process_record;
+        EXCEPTION WHEN OTHERS THEN
+            v_start := 1;
+        END;
+        EXECUTE IMMEDIATE 'CREATE SEQUENCE t_flow_sub_process_record_seq INCREMENT BY 50 START WITH ' || v_start;
+    END IF;
+END;
+/

flow-engine-starter-infra/src/main/java/com/codingapi/flow/infra/entity/FlowRecordEntity.java

@@ -11,7 +11,8 @@ public class FlowRecordEntity {
      * 记录id
      */
     @Id
-    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "flow_record_seq")
+    @SequenceGenerator(name = "flow_record_seq", sequenceName = "t_flow_record_seq", allocationSize = 50)
     private Long id;
     /**
      * 工作id

flow-engine-starter-infra/src/main/java/com/codingapi/flow/infra/entity/FlowTodoMargeEntity.java

@@ -9,7 +9,8 @@
 public class FlowTodoMargeEntity {
 
     @Id
-    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "flow_todo_marge_seq")
+    @SequenceGenerator(name = "flow_todo_marge_seq", sequenceName = "t_flow_todo_marge_seq", allocationSize = 50)
     private Long id;
     /**
      * 待办id

flow-engine-starter-infra/src/main/java/com/codingapi/flow/infra/entity/FlowTodoRecordEntity.java

@@ -14,7 +14,8 @@ public class FlowTodoRecordEntity {
      * <p>使用序列生成（而非数据库自增），配合 hibernate 批插，降低高频批量写表的 DB 往返。
      */
     @Id
-    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "flow_todo_record_seq")
+    @SequenceGenerator(name = "flow_todo_record_seq", sequenceName = "t_flow_todo_record_seq", allocationSize = 50)
     private Long id;
 
     /**

flow-engine-starter-infra/src/main/java/com/codingapi/flow/infra/entity/SubProcessRecordEntity.java

@@ -7,6 +7,7 @@
 import jakarta.persistence.GenerationType;
 import jakarta.persistence.Id;
 import jakarta.persistence.Lob;
+import jakarta.persistence.SequenceGenerator;
 import jakarta.persistence.Table;
 import jakarta.persistence.UniqueConstraint;
 import jakarta.persistence.Version;
@@ -28,7 +29,8 @@ public class SubProcessRecordEntity {
      * 主键，由序列生成（替代数据库自增，配合 hibernate 批插降低批量往返）
      */
     @Id
-    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "flow_sub_process_record_seq")
+    @SequenceGenerator(name = "flow_sub_process_record_seq", sequenceName = "t_flow_sub_process_record_seq", allocationSize = 50)
     private Long id;
 
     /**