目录
MyBatics Plus官网
1.AbstractWrapper说明:
QueryWrapper(LambdaQueryWrapper) 和 UpdateWrapper(LambdaUpdateWrapper) 的父类
用于生成 sql 的 where 条件, entity 属性也用于生成 sql 的 where 条件
注意: entity 生成的 where 条件与 使用各个 api 生成的 where 条件没有任何关联行为
2.allEq全部eq
allEq(Map<R, V> params)
allEq(Map<R, V> params, boolean null2IsNull)
allEq(boolean condition, Map<R, V> params, boolean null2IsNull)
个别参数说明:
params : key为数据库字段名,value为字段值null2IsNull : 为true则在map的value为null时调用 isNull 方法,为false时则忽略value为null的
- 例1:
allEq({id:1,name:"老王",age:null})--->id = 1 and name = '老王' and age is null - 例2:
allEq({id:1,name:"老王",age:null}, false)--->id = 1 and name = '老王'
allEq(BiPredicate<R, V> filter, Map<R, V> params)
allEq(BiPredicate<R, V> filter, Map<R, V> params, boolean null2IsNull)
allEq(boolean condition, BiPredicate<R, V> filter, Map<R, V> params, boolean null2IsNull)
个别参数说明:
filter : 过滤函数,是否允许字段传入比对条件中params 与 null2IsNull : 同上
- 例1:
allEq((k,v) -> k.indexOf("a") >= 0, {id:1,name:"老王",age:null})--->name = '老王' and age is null - 例2:
allEq((k,v) -> k.indexOf("a") >= 0, {id:1,name:"老王",age:null}, false)--->name = '老王'
3.eq等于
eq(R column, Object val)
eq(boolean condition, R column, Object val)
- 等于 =
- 例:
eq("name", "老王")--->name = '老王'
4.ne不等于
ne(R column, Object val)
ne(boolean condition, R column, Object val)
- 不等于 <>
- 例:
ne("name", "老王")--->name <> '老王'
5.gt大于
gt(R column, Object val)
gt(boolean condition, R column, Object val)
- 大于 >
- 例:
gt("age", 18)--->age > 18
6.ge大于等于
ge(R column, Object val)
ge(boolean condition, R column, Object val)
- 大于等于 >=
- 例:
ge("age", 18)--->age >= 18
7. lt小于
lt(R column, Object val)
lt(boolean condition, R column, Object val)
- 小于 <
- 例:
lt("age", 18)--->age < 18
8.le小于等于
le(R column, Object val)
le(boolean condition, R column, Object val)
- 小于等于 <=
- 例:
le("age", 18)--->age <= 18
9. between在区间内
between(R column, Object val1, Object val2)
between(boolean condition, R column, Object val1, Object val2)
- BETWEEN 值1 AND 值2
- 例:
between("age", 18, 30)--->age between 18 and 30
10.notBetween不在区间内
notBetween(R column, Object val1, Object val2)
notBetween(boolean condition, R column, Object val1, Object val2)
- NOT BETWEEN 值1 AND 值2
- 例:
notBetween("age", 18, 30)--->age not between 18 and 30
11.like模糊匹配
like(R column, Object val)
like(boolean condition, R column, Object val)
- LIKE '%值%'
- 例:
like("name", "王")--->name like '%王%'
12.notLike模糊不匹配
notLike(R column, Object val)
notLike(boolean condition, R column, Object val)
- NOT LIKE '%值%'
- 例:
notLike("name", "王")--->name not like '%王%'
13.likeLeft模糊左匹配
likeLeft(R column, Object val)
likeLeft(boolean condition, R column, Object val)
- LIKE '%值'
- 例:
likeLeft("name", "王")--->name like '%王'
14. likeRight模糊右匹配
likeRight(R column, Object val)
likeRight(boolean condition, R column, Object val)
- LIKE '值%'
- 例:
likeRight("name", "王")--->name like '王%'
15.isNull是否为null
isNull(R column)
isNull(boolean condition, R column)
- 字段 IS NULL
- 例:
isNull("name")--->name is null
16. isNotNull不等于null
isNotNull(R column)
isNotNull(boolean condition, R column)
- 字段 IS NOT NULL
- 例:
isNotNull("name")--->name is not null
17.in在范围期间
in(R column, Collection<?> value)
in(boolean condition, R column, Collection<?> value)
- 字段 IN (value.get(0), value.get(1), ...)
- 例:
in("age",{1,2,3})--->age in (1,2,3)
in(R column, Object... values)
in(boolean condition, R column, Object... values)
- 字段 IN (v0, v1, ...)
- 例:
in("age", 1, 2, 3)--->age in (1,2,3)
18.notIn不在区间内
notIn(R column, Collection<?> value)
notIn(boolean condition, R column, Collection<?> value)
- 字段 NOT IN (value.get(0), value.get(1), ...)
- 例:
notIn("age",{1,2,3})--->age not in (1,2,3)
notIn(R column, Object... values)
notIn(boolean condition, R column, Object... values)
- 字段 NOT IN (v0, v1, ...)
- 例:
notIn("age", 1, 2, 3)--->age not in (1,2,3)
19. inSql子sql语句
inSql(R column, String inValue)
inSql(boolean condition, R column, String inValue)
- 字段 IN ( sql语句 )
- 例:
inSql("age", "1,2,3,4,5,6")--->age in (1,2,3,4,5,6) - 例:
inSql("id", "select id from table where id < 3")--->id in (select id from table where id < 3)
20.notInSql不在sql内
notInSql(R column, String inValue)
notInSql(boolean condition, R column, String inValue)
- 字段 NOT IN ( sql语句 )
- 例:
notInSql("age", "1,2,3,4,5,6")--->age not in (1,2,3,4,5,6) - 例:
notInSql("id", "select id from table where id < 3")--->id not in (select id from table where id < 3)
21.groupBy组合排序
groupBy(R... columns)
groupBy(boolean condition, R... columns)
- 分组：GROUP BY 字段, ...
- 例:
groupBy("id", "name")--->group by id,name
22.orderByAsc升序
orderByAsc(R... columns)
orderByAsc(boolean condition, R... columns)
- 排序：ORDER BY 字段, ... ASC
- 例:
orderByAsc("id", "name")--->order by id ASC,name ASC
23.orderByDesc倒叙
orderByDesc(R... columns)
orderByDesc(boolean condition, R... columns)
- 排序：ORDER BY 字段, ... DESC
- 例:
orderByDesc("id", "name")--->order by id DESC,name DESC
24.orderBy排序
orderBy(boolean condition, boolean isAsc, R... columns)
- 排序：ORDER BY 字段, ...
- 例:
orderBy(true, true, "id", "name")--->order by id ASC,name ASC
25.having
having(String sqlHaving, Object... params)
having(boolean condition, String sqlHaving, Object... params)
- HAVING ( sql语句 )
- 例:
having("sum(age) > 10")--->having sum(age) > 10 - 例:
having("sum(age) > {0}", 11)--->having sum(age) > 11
26. func主要用于判断连不能断
func(Consumer<Children> consumer)
func(boolean condition, Consumer<Children> consumer)
- func 方法(主要方便在出现if...else下调用不同方法能不断链)
- 例:
func(i -> if(true) {i.eq("id", 1)} else {i.ne("id", 1)})
27.or或者
or()
or(boolean condition)
- 拼接 OR
注意事项:
主动调用or表示紧接着下一个方法不是用and连接!(不调用or则默认为使用and连接)
- 例:
eq("id",1).or().eq("name","老王")--->id = 1 or name = '老王'
or(Consumer<Param> consumer)
or(boolean condition, Consumer<Param> consumer)
- OR 嵌套
- 例:
or(i -> i.eq("name", "李白").ne("status", "活着"))--->or (name = '李白' and status <> '活着')
28. and
and(Consumer<Param> consumer)
and(boolean condition, Consumer<Param> consumer)
- AND 嵌套
- 例:
and(i -> i.eq("name", "李白").ne("status", "活着"))--->and (name = '李白' and status <> '活着')
29. nested
nested(Consumer<Param> consumer)
nested(boolean condition, Consumer<Param> consumer)
- 正常嵌套 不带 AND 或者 OR
- 例:
nested(i -> i.eq("name", "李白").ne("status", "活着"))--->(name = '李白' and status <> '活着')
30.apply
apply(String applySql, Object... params)
apply(boolean condition, String applySql, Object... params)
- 拼接 sql
注意事项:
该方法可用于数据库函数 动态入参的params对应前面applySql内部的{index}部分.这样是不会有sql注入风险的,反之会有!
- 例:
apply("id = 1")--->id = 1 - 例:
apply("date_format(dateColumn,'%Y-%m-%d') = '2008-08-08'")--->date_format(dateColumn,'%Y-%m-%d') = '2008-08-08'") - 例:
apply("date_format(dateColumn,'%Y-%m-%d') = {0}", "2008-08-08")--->date_format(dateColumn,'%Y-%m-%d') = '2008-08-08'")
31.last
last(String lastSql)
last(boolean condition, String lastSql)
- 无视优化规则直接拼接到 sql 的最后
注意事项:
只能调用一次,多次调用以最后一次为准 有sql注入的风险,请谨慎使用
- 例:
last("limit 1")
32.exists
exists(String existsSql)
exists(boolean condition, String existsSql)
- 拼接 EXISTS ( sql语句 )
- 例:
exists("select id from table where age = 1")--->exists (select id from table where age = 1)
33.notExists
notExists(String notExistsSql)
notExists(boolean condition, String notExistsSql)
- 拼接 NOT EXISTS ( sql语句 )
- 例:
notExists("select id from table where age = 1")--->not exists (select id from table where age = 1) - QueryWrapper
说明:
继承自 AbstractWrapper ,自身的内部属性 entity 也用于生成 where 条件
及 LambdaQueryWrapper, 可以通过 new QueryWrapper().lambda() 方法获取
34.select
select(String... sqlSelect)
select(Predicate<TableFieldInfo> predicate)
select(Class<T> entityClass, Predicate<TableFieldInfo> predicate)
- 设置查询字段
说明:
以上方分法为两类.
第二类方法为:过滤查询字段(主键除外),入参不包含 class 的调用前需要wrapper内的entity属性有值! 这两类方法重复调用以最后一次为准
- 例:
select("id", "name", "age") - 例:
select(i -> i.getProperty().startsWith("test"))
35.UpdateWrapper
说明:
继承自 AbstractWrapper ,自身的内部属性 entity 也用于生成 where 条件
及 LambdaUpdateWrapper, 可以通过 new UpdateWrapper().lambda() 方法获取!
# set
set(String column, Object val)
set(boolean condition, String column, Object val)
- SQL SET 字段
- 例:
set("name", "老李头") - 例:
set("name", "")--->数据库字段值变为空字符串 - 例:
set("name", null)--->数据库字段值变为null
# setSql
setSql(String sql)
- 设置 SET 部分 SQL
- 例:
setSql("name = '老李头'")
# lambda
- 获取
LambdaWrapper
在QueryWrapper中是获取LambdaQueryWrapper
在UpdateWrapper中是获取LambdaUpdateWrapper
上面主要是参考官网的内容，用于记录知识点即可