1、查找表中的重复记录，重复记录是根据单个字段（peopleId）来判断
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SELECT
*
FROM
people
WHERE
peopleId IN (
SELECT
peopleId
FROM
people
GROUP BY
peopleId
HAVING
count(peopleId) > 1
)
2、删除表中多余的重复记录，重复记录是根据单个字段（peopleId）来判断，只留有rowid最小的记录
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DELETE FROM
people
WHERE
peopleId IN (
SELECT
peopleId
FROM
people
GROUP BY
peopleId
HAVING
count(peopleId) > 1
)
AND rowid NOT IN (
SELECT
min(rowid)
FROM
people
GROUP BY
peopleId
HAVING
count(peopleId) > 1
)
3、查找表中多余的重复记录（多个字段）
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SELECT
*
FROM
vitae a
WHERE
(a.peopleId, a.seq) IN (
SELECT
peopleId,
seq
FROM
vitae
GROUP BY
peopleId,
seq
HAVING
count(*) > 1
)
4、删除表中多余的重复记录（多个字段），只留有rowid最小的记录
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DELETE FROM
vitae a
WHERE
(a.peopleId, a.seq) IN (
SELECT
peopleId,
seq
FROM
vitae
GROUP BY
peopleId,
seq
HAVING
count(*) > 1
)
AND rowid NOT IN (
SELECT
min(rowid)
FROM
vitae
GROUP BY
peopleId,
seq
HAVING
count(*) > 1
)
比方说，在A表中存在一个字段“name”，而且不同记录之间的“name”值有可能会相同，现在就需要查询出在该表中的各记录之间，“name”值存在重复的项
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SELECT
NAME,
Count(*)
FROM
A
GROUP BY
NAME
HAVING
Count(*) > 1
如果还查性别也相同大则如下
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SELECT
NAME,
sex,
Count(*)
FROM
A
GROUP BY
NAME,
sex
HAVING
Count(*) > 1