MyBaitsPlus--条件构造器Wrapper

逃离我推掉我的手 2021-08-26 23:07 483阅读 0赞

### AbstractWrapper ###

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

#### allEq ####

全部eq(或个别isNull)

allEq(Map<R, V> params)
    allEq(Map<R, V> params, boolean null2IsNull)
    allEq(boolean condition, Map<R, V> params, boolean null2IsNull)

*  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)

*  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'

#### eq ####

等于

eq(R column, Object val)
    eq(boolean condition, R column, Object val)

*  例: eq(“name”, “老王”)—>name = ‘老王’

#### ne ####

不等于

ne(R column, Object val)
    ne(boolean condition, R column, Object val)

*  例: ne(“name”, “老王”)—>name <> ‘老王’

#### gt ####

大于 >

ge(R column, Object val)
    ge(boolean condition, R column, Object val)

*  例: ge(“age”, 18)—>age >= 18

#### ge ####

大于等于

ge(R column, Object val)
    ge(boolean condition, R column, Object val)

*  例: ge(“age”, 18)—>age >= 18

#### lt ####

小于 <

lt(R column, Object val)
    lt(boolean condition, R column, Object val)

*  例: lt(“age”, 18)—>age < 18

#### le ####

小于等于 <=

le(R column, Object val)
    le(boolean condition, R column, Object val)

*  le(“age”, 18)—>age <= 18

#### between ####

BETWEEN 值1 AND 值2

between(R column, Object val1, Object val2)
    between(boolean condition, R column, Object val1, Object val2)

*  例: between(“age”, 18, 30)—>age between 18 and 30

#### notBetween ####

NOT BETWEEN 值1 AND 值2

notBetween(R column, Object val1, Object val2)
    notBetween(boolean condition, R column, Object val1, Object val2)

*  例: notBetween(“age”, 18, 30)—>age not between 18 and 30

#### like ####

LIKE ‘%值%’

like(R column, Object val)
    like(boolean condition, R column, Object val)

*  例: like(“name”, “王”)—>name like ‘%王%’

#### notLike ####

NOT LIKE ‘%值%’

notLike(R column, Object val)
    notLike(boolean condition, R column, Object val)

*  例: notLike(“name”, “王”)—>name not like ‘%王%’

#### likeLeft ####

LIKE ‘%值’

likeLeft(R column, Object val)
    likeLeft(boolean condition, R column, Object val)

*  例: likeLeft(“name”, “王”)—>name like ‘%王’

#### likeRight ####

LIKE ‘值%’

likeRight(R column, Object val)
    likeRight(boolean condition, R column, Object val)

*  例: likeRight(“name”, “王”)—>name like ‘王%’

#### isNull ####

字段 IS NULL

isNull(R column)
    isNull(boolean condition, R column)

*  例: isNull(“name”)—>name is null

#### isNotNull ####

字段 IS NOT NULL

isNotNull(R column)
    isNotNull(boolean condition, R column)

*  例: isNotNull(“name”)—>name is not null

#### in ####

字段 IN (value.get(0), value.get(1), …)

in(R column, Collection<?> value)
    in(boolean condition, R column, Collection<?> value)

*  例: in(“age”,\{1,2,3\})—>age in (1,2,3)

字段 IN (v0, v1, …)

in(R column, Object... values)
    in(boolean condition, R column, Object... values)

*  例: in(“age”, 1, 2, 3)—>age in (1,2,3)

#### notIn ####

字段 NOT IN (value.get(0), value.get(1), …)

notIn(R column, Collection<?> value)
    notIn(boolean condition, R column, Collection<?> value)

*  例: notIn(“age”,\{1,2,3\})—>age not in (1,2,3)

字段 NOT IN (v0, v1, …)

notIn(R column, Object... values)
    notIn(boolean condition, R column, Object... values)

*  例: notIn(“age”, 1, 2, 3)—>age not in (1,2,3)

#### inSql ####

用于嵌套查询：字段 IN (sql语句)

inSql(R column, String inValue)
    inSql(boolean condition, R column, String inValue)

*  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)

#### notInSql ####

字段 NOT IN (sql语句)

notInSql(R column, String inValue)
    notInSql(boolean condition, R column, String inValue)

*  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”)—>age not in (select id from table where id < 3)

#### groupBy ####

分组：GROUP BY 字段, …

groupBy(R... columns)
    groupBy(boolean condition, R... columns)

*  例: groupBy(“id”, “name”)—>group by id,name

#### orderByAse ####

排序：ORDER BY 字段, … ASC

orderByAsc(R... columns)
    orderByAsc(boolean condition, R... columns)

*  例: orderByAsc(“id”, “name”)—>order by id ASC,name ASC

#### orderByDesc ####

排序：ORDER BY 字段，… DESC

orderByDesc(R... columns)
    orderByDesc(boolean condition, R... columns)

*  例: orderBy(true, true, “id”, “name”)—>order by id ASC,name ASC

#### orderBy ####

排序 ORDER BY 字段, …

orderBy(boolean condition, boolean isAsc, R... columns)

*  例: orderBy(true, true, “id”, “name”)—>order by id ASC,name ASC

#### having ####

HAVING (sql语句)

having(String sqlHaving, Object... params)
    having(boolean condition, String sqlHaving, Object... params)

*  例: having(“sum(age) > 10”)—>having sum(age) > 10
 *  例: having(“sum(age) > \{0\}”, 11)—>having sum(age) > 11

#### or ####

拼接 OR  
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)

or()
    or(boolean condition)

*  例: eq(“id”,1).or().eq(“name”,“老王”)—>id = 1 or name = ‘老王’

OR 嵌套

*  例: or(i -> i.eq(“name”, “李白”).ne(“status”, “活着”))—>or (name = ‘李白’ and status <> ‘活着’)

#### and ####

AND 嵌套

and(Consumer<Param> consumer)
    and(boolean condition, Consumer<Param> consumer)

*  例: and(i -> i.eq(“name”, “李白”).ne(“status”, “活着”))—>and (name = ‘李白’ and status <> ‘活着’)

#### nested ####

正常嵌套 不带AND或者OR

nested(Consumer<Param> consumer)
    nested(boolean condition, Consumer<Param> consumer)

*  例: nested(i -> i.eq(“name”, “李白”).ne(“status”, “活着”))—>(name = ‘李白’ and status <> ‘活着’)

#### apply ####

拼接sql

apply(String applySql, Object... params)
    apply(boolean condition, String applySql, Object... params)

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’")

#### last ####

无视优化规则直接拼接到sql的最后

last(String lastSql)
    last(boolean condition, String lastSql)

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”)

#### exists ####

拼接EXISTS (sql语句)

exists(String existsSql)
    exists(boolean condition, String existsSql)

*  例: exists(“select id from table where age = 1”)—>exists (select id from table where age = 1)

#### notExists ####

拼接NOT EXISTS（sql语句）

notExists(String notExistsSql)
    notExists(boolean condition, String notExistsSql)