判断需要插入的数据是否存在,如果不存在就更新
MERGE INTO 表名 T1
USING (
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
) T2
/*判断是更新还是新记录的条件*/
ON (
T1./*判断数据是否重复的字段*/ = T2./*判断数据是否重复的字段*/
AND T1./*判断数据是否重复的字段*/ = T2./*判断数据是否重复的字段*/
)
/*数据存在则更新*/
WHEN MATCHED THEN
UPDATE SET T./*需要更新的字段*/=T1/*需要更新的字段*/
/*数据不存在则插入新记录*/
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)
例子:
MERGE INTO RES_SCHOOL_CLUB t1
USING (
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
) 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)
注意:很容易造成的一个错误是:
错误:更新或者插入时候写表名都是错误的!比如:UPDATE 表名 SET... 或者 INSERT INTO 表名(...)
正确:直接UPDATE SET...和INSERT VALUES (....)括号里填相应的字段,如果没有给空值.
错误:ON 后面缺少(),ORA-00969: missing ON keyword
正确:无论 ON 后面条件多少都添加()
另外网上还有提供两种方法:
方法一:mybatis批量插入oracle时需要显式指定为 useGeneratedKeys="false"
INSERT ALL
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}
)
SELECT 1 FROM DUAL
另外一种方法是 insert into table(...) (select ... from dual) union all (select ... from dual)
INSERT INTO T_APPLAUD
(
ID,
USER_ID,
BUSINESS_TYPE,
PRODUCT_ID,
CREATE_TIME
)
(
SELECT
#{item.id},
#{item.userId},
#{item.businessType},
#{item.productId},
#{item.createdTime}
FROM DUAL
)
补充:批量保存时候报错:ORA-01790: 表达式必须具有与对应表达式相同的数据类型
原因:由于参数为null,而批量保存时候不识别null为什么类型报错
解决:在相应参数中添加jdbcType: