sqlite与sqlserver区别

--sqlserver--
select Filed1+‘@‘+Filed2 from table

--sqlite--
select Filed1||‘@‘||Filed2 from table

--------添加字段----------

--sqlserver--
IF not exists 
    (select * from syscolumns where id=object_id(‘表名‘) and name=‘字段‘)
BEGIN
    alter table 表名 add 字段 int
end

--sqlite--
alter table 表名 add 字段 int


--------更改字段类型----------

--sqlserver--
alter table table alter column filed nvarchar(256)

--sqlite中需要把旧表重命名，创建新表(这个时候更改字段类型)，然后再把数据导入到新表中，删除旧表--
ALTER TABLE  表名  RENAME TO "重命名"

Create TABLE "表名"(
[Id] bigint NOT NULL
,[Name] nvarchar(16) 
, Primary Key(Id)   
)

Insert Into ‘重命名‘ ([Id],[Name])  Select [Id],[Name] From MAIN.[‘表名‘]

Drop Table MAIN.[重命名表]

--sqlsever--
SELECT TOP 10 * FROM table ORDER BY filed DESC

--sqlite--
select * from table limit 0,10

--sqlserver--
IF NOT EXISTS (select * from table where FID=6)  
BEGIN 
insert into table(FName,FIsDelete) select ‘t‘,0 
END

--sqlite--
insert into table(FName,FIsDelete)
select ‘tt‘,0 where not exists(
select * from table where FID=6
)