multiple-tables

问题 I've been searching in stack for similiar questions but I couldn't find one that helps me with this issue, or I couldn't understand it. I've got 3 tables. Users +---------+------+--------------+ | id_user | name | age | +---------+------+--------------+ | user1 | John | 51 | +---------+------+--------------+ | user2 | Jane | 65 | +---------+------+--------------+ | user3 | Katie| 51 | +---------+------+--------------+ | user4 | Marck| 65 | +---------+------+--------------+ City1 +---------+--

问题 I've been searching in stack for similiar questions but I couldn't find one that helps me with this issue, or I couldn't understand it. I've got 3 tables. Users +---------+------+--------------+ | id_user | name | age | +---------+------+--------------+ | user1 | John | 51 | +---------+------+--------------+ | user2 | Jane | 65 | +---------+------+--------------+ | user3 | Katie| 51 | +---------+------+--------------+ | user4 | Marck| 65 | +---------+------+--------------+ City1 +---------+--

问题 I am trying to write sub-queries so that I search all tables for a column named id and since there are multiple tables with id column, I want to add the condition, so that id = 3119093 . My attempt was: Select * from information_schema.tables where id = '3119093' and id IN ( Select table_name from information_schema.columns where column_name = 'id' ); This didn't work so I tried: Select * from information_schema.tables where table_name IN ( Select table_name from information_schema.columns

问题 I've got one master table, which has items stored in multiple levels, parents and childs, and there is a second table which may or may not have additional data. I need to query two levels from my master table and have a left join on my second table, but because of the ordering within my query this will not work. SELECT something FROM master as parent, master as child LEFT JOIN second as parentdata ON parent.secondary_id = parentdata.id LEFT JOIN second as childdata ON child.secondary_id =

问题 I've got one master table, which has items stored in multiple levels, parents and childs, and there is a second table which may or may not have additional data. I need to query two levels from my master table and have a left join on my second table, but because of the ordering within my query this will not work. SELECT something FROM master as parent, master as child LEFT JOIN second as parentdata ON parent.secondary_id = parentdata.id LEFT JOIN second as childdata ON child.secondary_id =

问题 Normally we create 1:1 mapping per table-class. Ex(Tables): [users] user_id - PK name [transactions] user_id - FK item_id amount Example mapping: public class User { public string ID {get; set;} public string Name {get; set;} } public class Transaction { public string UserID {get; set;} public string ItemID {get; set;} public Decimal Amount {get; set;} } But due to optimization concern and sometimes there are operations needed to be done while querying for results; we usually use stored

问题 SELECT A.CODE, B.NOTE, C.NUMBER FROM (A LEFT JOIN B ON A.CODE = B.CODE LEFT JOIN C ON A.CODE = C.NUMBER ) WHERE C.ID = B.ID Need to show some results combined from 3 tables, but my results show all data from table B reported also if the data isn't real from table C. Table A.code 1 2 3 Table B.code 1 2 3 Table B.note pippo paperino pluto Table C.number 1 Ideally there should be one result showing 1 1 pippo but in results it is shown: 1 1 pippo 1 1 paperino 1 1 pluto How can I get the real data

问题 I'm trying to run a query from a .NET page but I seem to having some problems with having multiple queries. My query is similar to this SELECT * FROM table1; SELECT * from table2 But i seem to get an invalid character error when executing this from a .Net page. It runs fine in SQL developer but only fails when i put it in my .NET page. I've added the BEGIN and END to the query as some websites suggest you need this to run multiple queries but then I get the following error ORA-06550: line 1,

问题 first I want to say I'm new at android, so I'm apologizing if the question is to stupid. I'm writting a Content Provider for a SQLite database with two tables. On table is to show a list at a navigation-drawer activity and the second table is to show in a ListFragment. Everytime when I'm starting the app I'm getting an SQLException. 10-07 15:30:33.856 28280-28813/de.schmidt.android.passworttresor E/SQLiteLog: (1) near "table": syntax error 10-07 15:30:33.871 28280-28813/de.schmidt.android

问题 first I want to say I'm new at android, so I'm apologizing if the question is to stupid. I'm writting a Content Provider for a SQLite database with two tables. On table is to show a list at a navigation-drawer activity and the second table is to show in a ListFragment. Everytime when I'm starting the app I'm getting an SQLException. 10-07 15:30:33.856 28280-28813/de.schmidt.android.passworttresor E/SQLiteLog: (1) near "table": syntax error 10-07 15:30:33.871 28280-28813/de.schmidt.android