where-clause | 易学教程

Update query cancelled by user

阅读更多关于 Update query cancelled by user

问题 I have a table that has millions of rows. Accidentally I wrote an update query over a table without where clause and clicked execute. It started executing. After two seconds I realized the query is wrong and I clicked ' Stop ' button in Sql Server Management Studio . The query execution was stopped, this all happened within 7 seconds. Now I am curious to know if there are any rows affected. If any which are they? How to find it? 回答1: A single update statement will not update some rows. It's

MySQL direct INSERT INTO with WHERE clause

阅读更多关于 MySQL direct INSERT INTO with WHERE clause

问题 I tried googling for this issue but only find how to do it using two tables, as follows, INSERT INTO tbl_member SELECT Field1,Field2,Field3,... FROM temp_table WHERE NOT EXISTS(SELECT * FROM tbl_member WHERE (temp_table.Field1=tbl_member.Field1 and temp_table.Field2=tbl_member.Field2...etc.) ) This worked for one scenario,But now my interest is to upload data directly from the program itself without using two tables. What i want is to upload the data which is not in the table. The sql i had

How do I append a 'where' clause using VB.NET and LINQ?

阅读更多关于 How do I append a 'where' clause using VB.NET and LINQ?

问题 I am pretty new to VB.NET and am having a bit of trouble here with something I thought should be simple. Keeping it simple, let's say I have a Document table with "Name" that I want to search on (in reality there are several other tables, joins, etc. ..). I need to be able to build the query using a where clause based on string values passed in. Example - the user may pass in "ABC", "ABC DEF", "ABC DEF GHI". The final query would be (the syntax is not correct, I know): Select * from Documents

MySQL Select last 7 days

阅读更多关于 MySQL Select last 7 days

I read some Posts here and seems like nothing special but I can not still select the entries of the last days. SELECT p1.kArtikel, p1.cName, p1.cKurzBeschreibung, p1.dLetzteAktualisierung, p1.dErstellt, p1.cSeo, p2.kartikelpict, p2.nNr, p2.cPfad FROM tartikel AS p1 WHERE DATE(dErstellt) > (NOW() - INTERVAL 7 DAY) INNER JOIN tartikelpict AS p2 ON (p1.kArtikel = p2.kArtikel) WHERE (p2.nNr = 1) ORDER BY p1.kArtikel DESC LIMIT 100;', $connection); If I add the between today and last 7 days my Code will not output anything. The WHERE clause is misplaced, it has to follow the table references and

How to write a SQL DELETE statement with a SELECT statement in the WHERE clause?

阅读更多关于 How to write a SQL DELETE statement with a SELECT statement in the WHERE clause?

Database: Sybase Advantage 11 On my quest to normalize data, I am trying to delete the results I get from this SELECT statement: SELECT tableA.entitynum FROM tableA q INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%/%/%') AND (u.FldFormat = 'Date') ; This is the DELETE statement I have come up with: DELETE FROM tableA WHERE (SELECT q.entitynum FROM tableA q INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%

why would you use WHERE 1=0 statement in SQL?

阅读更多关于 why would you use WHERE 1=0 statement in SQL?

问题 I saw a query run in a log file on an application. and it contained a query like: SELECT ID FROM CUST_ATTR49 WHERE 1=0 what is the use of such a query that is bound to return nothing? 回答1: A query like this can be used to ping the database. The clause: WHERE 1=0 Ensures that non data is sent back, so no CPU charge, no Network traffic or other resource consumption. A query like that can test for: server availability CUST_ATTR49 table existence ID column existence Keeping a connection alive

In Haskell, when do we use in with let?

阅读更多关于 In Haskell, when do we use in with let?

In the following code, the last phrase I can put an in in front. Will it change anything? Another question: If I decide to put in in front of the last phrase, do I need to indent it? I tried without indenting and hugs complains Last generator in do {...} must be an expression import Data.Char groupsOf _ [] = [] groupsOf n xs = take n xs : groupsOf n ( tail xs ) problem_8 x = maximum . map product . groupsOf 5 $ x main = do t <- readFile "p8.log" let digits = map digitToInt $concat $ lines t print $ problem_8 digits Edit Ok, so people don't seem to understand what I'm saying. Let me rephrase:

SQL WHERE condition is not equal to?

阅读更多关于 SQL WHERE condition is not equal to?

问题 Is it possible to negate a where clause? e.g. DELETE * FROM table WHERE id != 2; 回答1: You can do like this DELETE FROM table WHERE id NOT IN ( 2 ) OR DELETE FROM table WHERE id <> 2 As @Frank Schmitt noted, you might want to be careful about the NULL values too. If you want to delete everything which is not 2 (including the NULLs) then add OR id IS NULL to the WHERE clause. 回答2: Your question was already answered by the other posters, I'd just like to point out that delete from table where id

How to pass array values in where clause of mysql query?

阅读更多关于 How to pass array values in where clause of mysql query?

问题 I have a variable $element whose value is: Array ( [4] => easy [5] => easy [7] => easy [8] => will [9] => easy [10] => will ) I want to use this variable in my query : $sql = "SELECT * FROM questions where type='$element'"; $result = $conn->query($sql); if ($result->num_rows > 0) { // output data of each row while($row = $result->fetch_assoc()) { echo "id: " . $row["question_name"]. "<br>"; } } Actually I want to parse from each element of $element variable and present different output

SQL Filter criteria in join criteria or where clause which is more efficient

阅读更多关于 SQL Filter criteria in join criteria or where clause which is more efficient

I have a relatively simple query joining two tables. The "Where" criteria can be expressed either in the join criteria or as a where clause. I'm wondering which is more efficient. Query is to find max sales for a salesman from the beginning of time until they were promoted. Case 1 select salesman.salesmanid, max(sales.quantity) from salesman inner join sales on salesman.salesmanid =sales.salesmanid and sales.salesdate < salesman.promotiondate group by salesman.salesmanid Case 2 select salesman.salesmanid, max(sales.quantity) from salesman inner join sales on salesman.salesmanid =sales