在sqlite中加入多个表得到错误的输出

Question

你好朋友，我有 5 个 table 如下

property_master --> "p_id" , "p_name" , "p_address" , "p_city" , "p_state" ,"r_id"

property_unit -->"unit_id"   , "p_id"  , "unit_name"   ,"r_id"

unit_info -->    "unit_info_id"   ,"unit_id" INTEGER,"p_id"   ,"p_bathroom"  ,"p_bedroom"  ,"p_size"  ,"p_rent"  ,"p_isrent"  ,"u_note" ,"r_id" 

tanant_master -->  "t_id"   , "t_name"  ,"t_cell_no"  ,"t_phone_no"  ,"t_mail"  ,"t_deposit"   ,"r_id"

property_assign-->  "t_assign_id"   , "unit_info_id"  ,  "t_id"  , "t_start_date"  , "t_end_date"  , "  t_rent_due_day"  , "t_lease_alert"  , "t_status"  ,"r_id"

我的查询如下

SELECT property_master.p_id AS "PID",
property_master.p_name AS "PropertyName",
property_master.p_address AS "ProepertyAddress",
property_master.p_city AS "ProepertyCity",
property_master.p_state AS "ProepertyState",
property_master.p_country AS "ProepertyCountry",

property_unit.p_id AS "PUID",
property_unit.unit_name AS "UnitName",
property_unit.unit_id AS "UnitID",

unit_info.p_id AS "UNPID",
unit_info.p_bathroom AS "UNBath",
unit_info.p_bedroom AS "UNBEd",
unit_info.p_size AS "UNSize",
unit_info.p_rent AS "UNRent",
unit_info.u_note AS "UNNOte",

tanant_master.p_id AS "TPID",
tanant_master.t_name AS "TPID",

property_assign.unit_info_id AS "UNITINFOID",
property_assign.t_id AS "UNITINFOID",
property_assign.t_start_date AS "UNITINFOID",
property_assign.t_end_date AS "UNITINFOID"

FROM property_master , property_unit , unit_info ,tanant_master ,   property_assign where property_assign.unit_info_id=unit_info.unit_info_id

见上图，所有属性

的值都是重复的

我想要分配属性列表和租户列表，它在 proeprty _assign table 和 tanant_master table 中用于所有属性但是当我运行上面的查询是给我错误的输出不知道我该如何解决它？

Answer 1

据我所知

-> 如果你想从 n 个表中获取数据，你必须给出 n-1 个条件。

-> 你必须为所有表维护一个公用列，或者至少为每两个表维护一个公用列。

编辑 :

如果你有r_id作为所有5个表中的公共列然后写where条件如下

如果你的表是 t1,t2,t3,t4,t5 那么

"........WHERE t1.r_id=t2.r_id AND t1.r_id=t3.r_id AND t1.r_id=t4.r_id AND t1.r_id=t5.r_id";

希望对您有所帮助。

在sqlite中加入多个表得到错误的输出

getting wrong output with multiple tables join in sqlite

sqlite

android

join

multiple-tables