目前數(shù)據(jù)的種類非常多，每種數(shù)據(jù)都支持sql語句，但是大家發(fā)現(xiàn)沒有每種數(shù)據(jù)的SQL都有自己的語法特性，都是SQL語句都沒有一個(gè)特定的語法標(biāo)準(zhǔn)，導(dǎo)致開發(fā)人員在開發(fā)的過程中無法任意選庫（如果用自己不熟的庫都會(huì)要學(xué)習(xí)一遍SQL語法），主要是學(xué)習(xí)成本太高
那么有沒有一種工具能夠統(tǒng)一下sql語法規(guī)則，只要學(xué)一種sql語句就可以跨庫執(zhí)行，讓開發(fā)人員不用學(xué)習(xí)每種庫的SQL語句呢？
下面就給大家介紹一款開源工具 hisql源碼 hisql介紹
hisql查詢樣例
單表查詢
根據(jù)hisql語句通過ToSql()方法生成目標(biāo)sql的原生sql
var _sql = sqlClient.HiSql("select * from HTest01 where CreateTime>='2022-02-17 09:27:50' and CreateTime<='2022-03-22 09:27:50'").ToSql();
hisql生成的sqlserver 的sql 如下的所示
select [htest01].[SID],[htest01].[UName],[htest01].[Age],[htest01].[Salary],[htest01].[Descript],[htest01].[CreateTime],[htest01].[CreateName],[htest01].[ModiTime],[htest01].[ModiName] from [HTest01] as [HTest01]
where [htest01].[CreateTime] >= '2022-02-17 09:27:50.000' and [htest01].[CreateTime] <= '2022-03-22 09:27:50.000'
hisql生成MySQL的sql如下所示
select `htest01`.`SID`,`htest01`.`UName`,`htest01`.`Age`,`htest01`.`Salary`,`htest01`.`Descript`,`htest01`.`CreateTime`,`htest01`.`CreateName`,`htest01`.`ModiTime`,`htest01`.`ModiName` from `htest01` as `htest01`
where `htest01`.`CreateTime` >= '2022-02-17 09:27:50.000' and `htest01`.`CreateTime` <= '2022-03-22 09:27:50.000'
hisql生成postgresql 的sql下所示
select "htest01"."SID","htest01"."UName","htest01"."Age","htest01"."Salary","htest01"."Descript","htest01"."CreateTime","htest01"."CreateName","htest01"."ModiTime","htest01"."ModiName" from "HTest01" as "htest01"
where "htest01"."CreateTime" >= '2022-02-17 09:27:50.000' and "htest01"."CreateTime" <= '2022-03-22 09:27:50.000'
大家可以會(huì)問 明明是"select * from HTest01 where CreateTime>='2022-02-17 09:27:50' and CreateTime<='2022-03-22 09:27:50'" 用的*查詢 生成的sql語句為什么會(huì)直接列出所有字段呢？ 熟HiSql的網(wǎng)友都應(yīng)該知道這里其實(shí)隱藏了一個(gè)功能就是用戶可以自定義字段排序在系統(tǒng)表Hi_FieldModel 中可配置
group by查詢
hisql 默認(rèn)支持的常用函數(shù) max,count,min,sum,avg
string sql = sqlClient.HiSql("select FieldName, count(FieldName) as NAME_count,max(FieldType) as FieldType_max from Hi_FieldModel group by FieldName").ToSql();
hisql生成的sqlserver 的sql 如下的所示
select [hi_fieldmodel].[FieldName],count(*) as NAME_count,max([hi_fieldmodel].[FieldType]) as FieldType_max from [Hi_FieldModel] as [Hi_FieldModel]
group by [hi_fieldmodel].[FieldName]
hisql生成mysql的sql如下所示
select `hi_fieldmodel`.`FieldName`,count(*) as NAME_count,max(`hi_fieldmodel`.`FieldType`) as FieldType_max from `Hi_FieldModel` as `hi_fieldmodel`
group by `hi_fieldmodel`.`FieldName`
hisql生成postgresql 的sql下所示
select "hi_fieldmodel"."FieldName",count(*) as NAME_count,max("hi_fieldmodel"."FieldType") as FieldType_max from "Hi_FieldModel" as "hi_fieldmodel"
group by "hi_fieldmodel"."FieldName"
having 查詢
上次有網(wǎng)友說having 實(shí)現(xiàn)起來很麻煩通過正則表達(dá)式解析很難實(shí)現(xiàn)，我只能說很多網(wǎng)友對正則表達(dá)式的理解還不是很深，正則表達(dá)式已經(jīng)應(yīng)用于種類型的編譯器中，下面就來演示一下Having
string sql_having = sqlClient.HiSql("select FieldName, count(FieldName) as NAME_count,max(FieldType) as FieldType_max from Hi_FieldModel group by FieldName having count(FieldName) > 1").ToSql();
hisql生成的sqlserver 的sql 如下的所示
select [hi_fieldmodel].[FieldName],count(*) as NAME_count,max([hi_fieldmodel].[FieldType]) as FieldType_max from [Hi_FieldModel] as [Hi_FieldModel]
group by [hi_fieldmodel].[FieldName]
having count(*) > 1
hisql生成mysql的sql如下所示
select `hi_fieldmodel`.`FieldName`,count(*) as NAME_count,max(`hi_fieldmodel`.`FieldType`) as FieldType_max from `Hi_FieldModel` as `hi_fieldmodel`
group by `hi_fieldmodel`.`FieldName`
having count(*) > 1
hisql生成postgresql 的sql下所示
select "hi_fieldmodel"."FieldName",count(*) as NAME_count,max("hi_fieldmodel"."FieldType") as FieldType_max from "Hi_FieldModel" as "hi_fieldmodel"
group by "hi_fieldmodel"."FieldName"
having count(*) > 1
join 多表查詢
hisql inner join 和 in 操作語法
var sql = sqlClient.HiSql("select a.tabname from hi_fieldmodel as a inner join Hi_TabModel as b on a.tabname =b.tabname inner join Hi_TabModel as c on a.tabname=c.tabname where a.tabname='h_test' and a.FieldType in (11,41,21) ").ToSql();
hisql生成的sqlserver 的sql 如下的所示
select [a].[TabName] from [Hi_FieldModel] as [a]
inner join [Hi_TabModel] as [b] on [a].[TabName] = [b].[TabName] inner join [Hi_TabModel] as [c] on [a].[TabName] = [c].[TabName]
where [a].[TabName] = 'h_test' and [a].[FieldType] in (11,41,21)
hisql生成mysql的sql如下所示
select `a`.`TabName` from `Hi_FieldModel` as `a`
inner join `Hi_TabModel` as `b` on `a`.`TabName` = `b`.`TabName` inner join `Hi_TabModel` as `c` on `a`.`TabName` = `c`.`TabName`
where `a`.`TabName` = 'h_test' and `a`.`FieldType` in (11,41,21)
hisql生成postgresql 的sql下所示
select "a"."TabName" from "Hi_FieldModel" as "a"
inner join "Hi_TabModel" as "b" on "a"."TabName" = "b"."TabName" inner join "Hi_TabModel" as "c" on "a"."TabName" = "c"."TabName"
where "a"."TabName" = 'h_test' and "a"."FieldType" in (11,41,21)
分頁
hisql 分頁 只要在日常查詢上增加Take() 每頁顯示多少數(shù)據(jù) Skip() 顯示第幾頁
var sql = sqlClient.HiSql("select a.tabname from hi_fieldmodel as a inner join Hi_TabModel as b on a.tabname =b.tabname inner join Hi_TabModel as c on a.tabname=c.tabname where a.tabname='h_test' and a.FieldType in (11,41,21) ").Take(2).Skip(2).ToSql();
hisql生成的sqlserver 的sql 如下的所示
select [TabName] from (
select ROW_NUMBER() OVER(Order by [a].[FieldType] ASC) AS _hi_rownum_, [a].[TabName] from [Hi_FieldModel] as [a]
inner join [Hi_TabModel] as [b] on [a].[TabName] = [b].[TabName] inner join [Hi_TabModel] as [c] on [a].[TabName] = [c].[TabName]
where [a].[TabName] = 'h_test' and [a].[FieldType] in (11,41,21)
) as hi_sql
where hi_sql._hi_rownum_ BETWEEN (2-1)*2+1 and 2*2 order by _hi_rownum_ asc
hisql生成mysql的sql如下所示
select `TabName` from (
select ROW_NUMBER() OVER(Order by `a`.`FieldType` ASC) AS `_hi_rownum_`, `a`.`TabName` from `Hi_FieldModel` as `a`
inner join `Hi_TabModel` as `b` on `a`.`TabName` = `b`.`TabName` inner join `Hi_TabModel` as `c` on `a`.`TabName` = `c`.`TabName`
where `a`.`TabName` = 'h_test' and `a`.`FieldType` in (11,41,21)
) as hi_sql
order by `_hi_rownum_` asc
limit 2,2
hisql生成postgresql 的sql下所示
select "TabName" from (
select ROW_NUMBER() OVER(Order by "a"."FieldType" ASC) AS "_hi_rownum_", "a"."TabName" from "Hi_FieldModel" as "a"
inner join "Hi_TabModel" as "b" on "a"."TabName" = "b"."TabName" inner join "Hi_TabModel" as "c" on "a"."TabName" = "c"."TabName"
where "a"."TabName" = 'h_test' and "a"."FieldType" in (11,41,21)
) as hi_sql
order by "_hi_rownum_" asc
limit 2 OFFSET 2
hisql 實(shí)現(xiàn)參數(shù)化
參數(shù)化可以有效的防注入，通過前端可以拼接的hisql語句通過參數(shù)化的方式傳入， 這樣就解決了注入問題
string sql1= sqlClient.HiSql("select * from hi_tabmodel where tabname=@tabname ", new { TabName="H_test" ,FieldName="DID"}).ToSql();
string sql2= sqlClient.HiSql("select * from hi_tabmodel where tabname=@tabname or TabType in( @TabType)", new { TabName="H_test" , TabType =new List<int> { 1,2,3,4} }).ToSql();
string sql3 = sqlClient.HiSql("select * from hi_tabmodel where tabname=@tabname ", new Dictionary<string, object> { { "TabName", "H_test" } }).ToSql();
鏈?zhǔn)讲樵?/h1>
hisql除了提供hisql語法外還提供鏈?zhǔn)讲樵兎椒ㄈ缦滤?/p>
string sql = sqlClient.Query("Hi_FieldModel").As("A").Field("A.FieldType")
.Join("Hi_TabModel").As("B").On(new HiSql.JoinOn() { { "A.TabName", "B.TabName" } })
.Where("A.TabName='GD_UniqueCodeInfo'").Group(new GroupBy { { "A.FieldType" } })
.Sort("A.FieldType asc", "A.TabName asc")
.Take(2).Skip(2)
.ToSql();
hisql語句和鏈?zhǔn)讲樵兓煊?/h1>
string sql = sqlClient.HiSql("select A.FieldType from Hi_FieldModel as A ")
.Where("A.TabName='GD_UniqueCodeInfo'").Group(new GroupBy { { "A.FieldType" } })
.Sort("A.FieldType asc", "A.TabName asc")
.Take(2).Skip(2)
.ToSql();
string sql = sqlClient.HiSql("select A.FieldType from Hi_FieldModel as A ")
.Where("A.TabName='GD_UniqueCodeInfo'").Group(new GroupBy { { "A.FieldType" } })
.Sort("A.FieldType asc", "A.TabName asc")
.Take(2).Skip(2)
.ToSql();
文章來自
https://www.cnblogs.com/tansar/p/16442741.html
