publicvoidabs(int id){ // 绝对值 select abs(poet_id) from poetry where id = xxx Record1<Integer> ans = dsl.select(DSL.abs(poetryTable.POET_ID)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
2. sqrt
开方
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publicvoidsqrt(int id){ // 开方 select sqrt(poet_id) from poetry where id = xxx Record1<BigDecimal> ans = dsl.select(DSL.sqrt(poetryTable.POET_ID)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
3. pow
n次方
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publicvoidpow(int id){ // n次方 select pow(poet_id, 2) from poetry where id = xxx Record1<BigDecimal> ans = dsl.select(poetryTable.POET_ID.pow(2)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
4. mod
求余
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publicvoidmode(int id){ // 求余数,select mod(poet_id, 2) from poetry where id = xxx Record1<Integer> ans = dsl.select(poetryTable.POET_ID.mod(2)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
5. ceil, floor, round
浮点数的取整处理
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publicvoidceil(int id){ // 向上取整,select ceil(poet_id) from poetry where id = xxx // floor 向下取整 // round 四舍五入 Record1<Integer> ans = dsl.select(DSL.ceil(poetryTable.POET_ID)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
6. rand
随机数
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publicvoidrand(int id){ // 随机数 select rand() from poetry where id = xxx Record1<BigDecimal> ans = dsl.select(DSL.rand()).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
7. length
字符串长度
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publicvoidstrLen(int id){ // 字符串长度 select length(`content`) from poetry where id = xxx Record1<Integer> ans = dsl.select(DSL.length(poetryTable.CONTENT)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
8. concat
字符串拼接
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publicvoidstrConcat(int id){ // 拼接 select concat(title, '--后缀') from poetry where id = xxx Record1<String> ans = dsl.select(DSL.concat(poetryTable.TITLE, "--后缀")).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
9. replace
字符串替换
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publicvoidreplace(int id){ // 替换字符串 select replace(title, '落日', '一灰灰') from poetry where id = xxx Record1<String> ans = dsl.select(DSL.replace(poetryTable.TITLE, "落日", "一灰灰")).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
10. lower, upper
字符串大小写转换
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publicvoidlowerUpper(int id){ // 转小写 select lower(title) from poetry where id = xxx // 转大写 select upper(title) from poetry where id = xxx Record1<String> ans = dsl.select(DSL.lower(poetryTable.TITLE)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
11. left, right
字符串左右截取
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publicvoidleftRight(int id){ // 左侧截取n个字符 select left(title, n) from poetry where id = xxx // 右侧截取n个字符 select right(title, n) from poetry where id = xxx Record1<String> ans = dsl.select(DSL.left(poetryTable.TITLE, 2)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1());
ans = dsl.select(DSL.right(poetryTable.TITLE, 2)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
12. trim
去掉收尾空白字符
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publicvoidtrim(int id){ // 去掉两端空格 select rim(title) from poetry where id = xxx Record1<String> ans = dsl.select(DSL.trim(poetryTable.TITLE)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); }
13. reverse
字符串反转
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publicvoidreverse(int id){ try { // fixme 请注意 h2database 不支持reverse 函数; mysql可以 // 字符串反转 select reverse(title) from poetry where id = xxx Record1<String> ans = dsl.select(DSL.reverse(poetryTable.TITLE)).from(poetryTable).where(poetryTable.ID.eq(id)).fetchOne(); System.out.println(ans.component1()); } catch (Exception e) { System.out.println(e.getMessage()); } }