inner-join

问题 UPDATE t1 SET t1.name=t2.name, t1.fb_id=t2.fb_id FROM nullemail t1 INNER JOIN run1 t2 ON t1.email=t2.email; Can someone please tell me what is wrong with this syntax? I have 2 tables. nullemail and run1. I want to update nullemail's columns( fb_id and name ) when the email id in nullemail is the same as run1. 回答1: UPDATE nullemail t1, run1 t2 SET t1.name=t2.name, t1.fb_id=t2.fb_id where t1.email=t2.email; Try this 来源： https://stackoverflow.com/questions/17802921/sql-syntax-update-after-inner

问题 I have three mysql tables items =========== id title items_in_categories ============================ id item_id category_id categories =========== id title I want to find all the items that belong to ALL the stated categories. Not any one category, but ALL categories Eg, if I want to search all the items that belongs to category id 3 and 5 the no. of possible categories to be searched can go up to as many as 20. Eg, I want to get all the items that belongs to category id 1, 2, 3, 4, 5, 6, ..

问题 This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center. Closed 6 years ago . table clsown id cls_id users_id 1----1---------1 2----1---------2 sql select cls_id, cls_name, MAX(case when rn = 1 then users_id end) user_id1, MAX(case

问题 The following code snippets should do the same work. SELECT t1.* FROM table1 t1 INNER JOIN table2 t2 ON t1.ID = t2.IDService WHERE t2.Code = @code and SELECT * FROM table1 t1 WHERE t1.ID IN (SELECT IDService FROM table2 WHERE Code = @code) Which one is the best solution, in general? And computationally, is better have two nested select or is better use inner join? EDIT: Consider that the PK of table1 is ID and the PK of table2 id the couple ( IDService,Code ). So, fixing the Code (using WHERE

问题 I'll use the following query to illustrate my question: select a.shipperid, b.orderid, b.custid from shippers a inner join orders b on a.shipperid = b.shipperid Shipperid is the primary key in the shippers table, and it is also the foreign key in the orders table. There are only three shipping IDs, and each of them is associated with many different orders in the order table. The join will match the tables when the shipper IDs match. However, each of the shipper IDs in the shippers table is

问题 I have a fairly simple join for three tables that is not returning any results. If I modify slightly I get sometime that appears jumbled (same data values in two fields). There is a Documents table from which I need the filename, a Variable table which has the variable definitions and names, and lastly I have a VariableValue table that the values for the variables are stored in. I am trying to get two values for each filename. Subject and Author. Here is the SQL call. SELECT DISTINCT

问题 I have two tables Ticket and Flight . One flight could have many tickets. I want to show fields departure_date , destination_date from the table Flight and name , surname from the table Ticket . And show data only for the certain flight_id . I use findBy method. Entity Flight @Entity @Table(name = "flight") public class Flight { @Id @GeneratedValue(strategy = GenerationType.AUTO) private Integer flight_id; @Column(name = "departureDate") private Date departureDate; @Column(name =

问题 I'm using JavaDB and working with two tables in the same database. I'm trying to update the PrevSales column in the "SalesResp" table with the values that are in the "SellDate" column of the "Vehicles" table when the Vehicle table's SellDate is before a the specified date. I'm matching the data between the two tables by using the "VIN" column that is present in both tables. I continually get errors surrounding the inner join in my code, SQL state 42x01. UPDATE SALESRESP JOIN VEHICLES ON

问题 The query below does its job to select the min, max, start and last price per day in a given month. I would like to select the same but for the whole month, as in show the overall performance for the given month instead of on a daily basis. Fiddle: http://sqlfiddle.com/#!9/ca4867/10 SELECT maxminprice.metal_id, maxminprice.metal_price_datetime_IST, maxminprice.max_price, maxminprice.min_price, firstlastprice.first_price, firstlastprice.last_price FROM (SELECT metal_id, DATE(metal_price

问题 Evening, I am trying to get an output of rows that are limited to n per group in MySQL. I can get it to work without joins, but with it I am just shy. I've pasted a dump of the relevant tables here: http://pastebin.com/6F0v1jhZ The query I am using is: SELECT title, catRef, RowNum, pCat, tog FROM ( SELECT title, catRef, @num := IF(@prevCat=catRef,@num+1,1) AS RowNum, @prevCat AS tog, @prevCat := catRef AS pCat FROM (select @prevCat:=null) AS initvars CROSS JOIN ( SELECT p.title, oi.catRef