初始化

sql/query_duplicate_records.sql

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+-- 查询重复记录的SQL语句集合
+-- 适用于SQL Server数据库
+
+-- 1. 查询stockin表中stockin_id重复的记录
+-- 显示重复的stockin_id及其出现次数
+SELECT 
+    stockin_id,
+    COUNT(*) as duplicate_count
+FROM stockin 
+GROUP BY stockin_id 
+HAVING COUNT(*) > 1
+ORDER BY duplicate_count DESC;
+
+-- 2. 查询stockin表中stockin_id重复的详细记录
+-- 显示所有重复记录的完整信息
+SELECT 
+    s1.*
+FROM stockin s1
+INNER JOIN (
+    SELECT stockin_id
+    FROM stockin
+    GROUP BY stockin_id
+    HAVING COUNT(*) > 1
+) s2 ON s1.stockin_id = s2.stockin_id
+ORDER BY s1.stockin_id, s1.create_date DESC;
+
+-- 3. 查询stockin表中除了最新记录外的重复记录（用于删除重复数据）
+-- 基于create_date字段保留最新的记录
+WITH RankedRecords AS (
+    SELECT 
+        *,
+        ROW_NUMBER() OVER (PARTITION BY stockin_id ORDER BY create_date DESC) as rn
+    FROM stockin
+)
+SELECT 
+    stockin_guid,
+    stockin_id,
+    create_date,
+    rn as record_rank
+FROM RankedRecords
+WHERE rn > 1  -- 显示除最新记录外的重复记录
+ORDER BY stockin_id, create_date DESC;
+
+-- 4. 通用模板：查询任意表的重复记录
+-- 使用示例：将table_name和column_name替换为实际的表名和字段名
+/*
+SELECT 
+    column_name,
+    COUNT(*) as duplicate_count
+FROM table_name 
+GROUP BY column_name 
+HAVING COUNT(*) > 1
+ORDER BY duplicate_count DESC;
+*/
+
+-- 5. 查询多个字段组合的重复记录
+-- 示例：查询stockin表中stockin_id和asn组合重复的记录
+SELECT 
+    stockin_id,
+    asn,
+    COUNT(*) as duplicate_count
+FROM stockin 
+GROUP BY stockin_id, asn 
+HAVING COUNT(*) > 1
+ORDER BY duplicate_count DESC;
+
+-- 6. 删除重复记录的SQL（谨慎使用，建议先备份数据）
+-- 保留最新的记录，删除旧的重复记录
+/*
+WITH RankedRecords AS (
+    SELECT 
+        stockin_guid,
+        ROW_NUMBER() OVER (PARTITION BY stockin_id ORDER BY create_date DESC) as rn
+    FROM stockin
+)
+DELETE FROM stockin 
+WHERE stockin_guid IN (
+    SELECT stockin_guid 
+    FROM RankedRecords 
+    WHERE rn > 1
+);
+*/
+
+-- 注意事项：
+-- 1. 在执行删除操作前，请务必备份数据
+-- 2. 建议先在测试环境中验证SQL语句的正确性
+-- 3. 可以根据实际业务需求调整排序字段和保留策略
+-- 4. 对于大表，建议分批处理以避免锁表时间过长