• pg_sql常用查询语句整理


    #pg_sql之增删改查
    
    #修改:
    inset into table_name
    (id,
    name,
    age,
    address
    )
    select
    replace(old_id,old_id,new_id),#old_id字段的old_id数据,替换为new_id
    replace(name,name,substring(concat('【新名字】'),name),1,20)),#name字段替换为【新名字】+name
    20,
    address
    from
        table_name
    where
        id ='201901'
    
    #增加
    inset into table_name
    (id,
    name,
    age,
    address,
    date
    )
    values(
    '201901',
    'xiaoming',
    '23',
    '上海',
    TO_DATE('2006-03-01','YYYY-MM-DD'))
    
    #更新
    update table_name
        set id =3
        where id = 2 and name ='xiaoming'
    
    #联表搜索 join on
    mybatis注解多条件查询
    @Selct({"<script>"+"查询语句"+"</script>"})
    List<DemoBo> getListByForm(Page<DemoBo> page,DemoForm demoForm)
    查询语句如下:
    
    select
        A.id,
        B.name,
        A.address,
        A.age
    from table_nameA as A
        left join table_nameB as B on A.id = B.id
    where A.id = 0
        <if test 'id != null'> and A.id <![CDATA[=]]> #{id}</if>
        <if test 'name != null'> and A.name <![CDATA[=]]> #{name}</if>
    order by A.age desc,A.id desc
    
    #条件判断 case when
    selct a.id ,a.name,a.age
        case when
            b.begindate = b.enddate
            then 1
            else 0
        end as f_date
    from table_nameA as a
        inner join(
                selct id,
                count(*) as count,
                sum(case when age =2 then 1 else 0 end) as age
                from table_nameB
                group by id
            ) as b on a.id = b.id
    where a.id =1232
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    转载 MySql常用查询语句(23种)
  • 原文地址:https://www.cnblogs.com/smuxiaolei/p/10847385.html
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