判斷需要插入的數據是否存在,如果不存在就更新
<insert id="saveBatch" parameterType="java.util.List" >
MERGE INTO 表名 T1
USING (
<foreach collection="list" item="item" index="index" separator="union" >
SELECT
SYS_GUID() AS CODE,
#{item.createDate,jdbcType=VARCHAR} AS CREATE_DATE,
#{item.createBy,jdbcType=VARCHAR} AS CREATE_BY,
#{item.flagDel,jdbcType=CHAR} AS FLAG_DEL,
#{item.flagDisplay,jdbcType=CHAR} AS FLAG_DISPLAY,
#{item.sort,jdbcType=DECIMAL} AS SORT
FROM DUAL
</foreach>) T2
/*判斷是更新還是新記錄的條件*/
ON (
T1./*判斷數據是否重複的字段*/ = T2./*判斷數據是否重複的字段*/
AND T1./*判斷數據是否重複的字段*/ = T2./*判斷數據是否重複的字段*/
)
/*數據存在則更新*/
WHEN MATCHED THEN
UPDATE SET T./*需要更新的字段*/=T1/*需要更新的字段*/
/*數據不存在則插入新記錄*/
WHEN NOT MATCHED THEN
INSERT
(CODE,CREATE_DATE,CREATE_BY,FLAG_DEL,FLAG_DISPLAY,SORT)
VALUES
(T2.CODE,T2.CREATE_DATE,T2.CREATE_BY,T2.FLAG_DEL,T2.FLAG_DISPLAY,T2.SORT)
</insert>
例子:
<insert id="batchSave" parameterType="java.util.List">
MERGE INTO RES_SCHOOL_CLUB t1
USING (
<foreach collection="list" item="item" index="index" separator="union" >
select
#{item.id,jdbcType=VARCHAR} ID,
#{item.clsSchoolId,jdbcType=VARCHAR} CLS_SCHOOL_ID,
#{item.originSchoolId,jdbcType=VARCHAR} ORIGIN_SCHOOL_ID,
#{item.resourceId,jdbcType=VARCHAR} RESOURCE_ID,
#{item.clsClubId,jdbcType=VARCHAR} CLS_CLUB_ID,
#{item.baseAreaId,jdbcType=VARCHAR} BASE_AREA_ID,
#{item.createTime,jdbcType=TIMESTAMP} CREATE_TIME
from dual
</foreach>) t2
ON (
t1.CLS_SCHOOL_ID = t2.CLS_SCHOOL_ID
AND t1.RESOURCE_ID = t2.RESOURCE_ID
)
WHEN MATCHED THEN
UPDATE SET t.CREATE_TIME = t1.CREATE_TIME
WHEN NOT MATCHED THEN
INSERT
(ID, CLS_SCHOOL_ID, ORIGIN_SCHOOL_ID, RESOURCE_ID, CLS_CLUB_ID, BASE_AREA_ID, CREATE_TIME)
VALUES
(t2.ID, t2.CLS_SCHOOL_ID, t2.ORIGIN_SCHOOL_ID, t2.RESOURCE_ID, t2.CLS_CLUB_ID, t2.BASE_AREA_ID, t2.CREATE_TIME)
</insert>
注意:很容易造成的一個錯誤是:
錯誤:更新或者插入時候寫表名都是錯誤的!比如:UPDATE 表名 SET... 或者 INSERT INTO 表名(...)
正確:直接UPDATE SET...和INSERT VALUES (....)括號裏填相應的字段,如果沒有給空值.
錯誤:ON 後面缺少(),ORA-00969: missing ON keyword
正確:無論 ON 後面條件多少都添加()
另外網上還有提供兩種方法:
方法一:mybatis批量插入oracle時需要顯式指定爲 useGeneratedKeys="false"
<insert id="addList" parameterType="java.util.List" useGeneratedKeys="false">
INSERT ALL
<foreach item="item" index="index" collection="list">
INTO T_APPLAUD
(
ID,
USER_ID,
BUSINESS_TYPE,
PRODUCT_ID,
CREATE_TIME
) VALUES
(
#{item.id, jdbcType=NUMERIC},
#{item.userId, jdbcType=VARCHAR},
#{item.businessType, jdbcType=VARCHAR},
#{item.productId, jdbcType=VARCHAR},
#{item.createdTime, jdbcType=NUMERIC}
)
</foreach>
SELECT 1 FROM DUAL
</insert>
另外一種方法是 insert into table(...) (select ... from dual) union all (select ... from dual)
<insert id="addList" parameterType="java.util.List" useGeneratedKeys="false">
INSERT INTO T_APPLAUD
(
ID,
USER_ID,
BUSINESS_TYPE,
PRODUCT_ID,
CREATE_TIME
)
<foreach item="item" index="index" collection="list" separator="union all">
(
SELECT
#{item.id},
#{item.userId},
#{item.businessType},
#{item.productId},
#{item.createdTime}
FROM DUAL
)
</foreach>
</insert>
補充:批量保存時候報錯:ORA-01790: 表達式必須具有與對應表達式相同的數據類型
原因:由於參數爲null,而批量保存時候不識別null爲什麼類型報錯
解決:在相應參數中添加jdbcType: