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How to insert an element after another element in JavaScript without using a library?

... than the insertBefore (break even if the existing node variable name is 3 chars long) Downsides: lower browser support since newer: https://caniuse.com/#feat=insert-adjacent will lose properties of the element such as events because outerHTML converts the element to a string. We need it because...
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MySQL Error 1093 - Can't specify target table for update in FROM clause

...s question In MySQL, you can't modify the same table which you use in the SELECT part. This behaviour is documented at: http://dev.mysql.com/doc/refman/5.6/en/update.html Maybe you can just join the table to itself If the logic is simple enough to re-shape the query, lose the subquery and join th...
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How to add column if not exists on PostgreSQL?

...s, _col text, _type regtype) RETURNS bool AS $func$ BEGIN IF EXISTS (SELECT 1 FROM pg_attribute WHERE attrelid = _tbl AND attname = _col AND NOT attisdropped) THEN RETURN FALSE; ELSE EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...
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How can I select and upload multiple files with HTML and PHP, using HTTP POST?

... </body> </html> Here's what it looks like in Chrome after selecting 2 items in the file dialog: And here's what it looks like after clicking the "Upload" button. This is just a sketch of a fully working answer. See PHP Manual: Handling file uploads for more information on prop...
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Truncating all tables in a Postgres database

...e IN VARCHAR) RETURNS void AS $$ DECLARE statements CURSOR FOR SELECT tablename FROM pg_tables WHERE tableowner = username AND schemaname = 'public'; BEGIN FOR stmt IN statements LOOP EXECUTE 'TRUNCATE TABLE ' || quote_ident(stmt.tablename) || ' CASCADE;'; END LOO...
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SQL Call Stored Procedure for each Row without using a cursor

...rate over all customers WHILE (1 = 1) BEGIN -- Get next customerId SELECT TOP 1 @CustomerID = CustomerID FROM Sales.Customer WHERE CustomerID > @CustomerId ORDER BY CustomerID -- Exit loop if no more customers IF @@ROWCOUNT = 0 BREAK; -- call your sproc EXEC dbo.YOURSPROC...
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How do I obtain a Query Execution Plan in SQL Server?

...ution plan in SQL Server Management Studio, or right click on the plan and select "Save Execution Plan As ..." to save the plan to a file in XML format. Method 2 - Using SHOWPLAN options This method is very similar to method 1 (in fact this is what SQL Server Management Studio does internally), ho...
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How to change column order in a table using sql query in sql server 2005?

... to look at the data in a table with a given column order when you make a "SELECT *". I'm a developer and do this kind of queries all the time. You can spare some time with a good pre-defined column order. From any other standpoint, of course, it has no sense: nothing should depend on the column ord...
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In SQL, how can you “group by” in ranges?

...version. Here are the correct versions of both of them on SQL Server 2000. select t.range as [score range], count(*) as [number of occurences] from ( select case when score between 0 and 9 then ' 0- 9' when score between 10 and 19 then '10-19' else '20-99' end as range from scores)...
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What makes a SQL statement sargable?

...non-sargable is to include a field inside a function in the where clause: SELECT ... FROM ... WHERE Year(myDate) = 2008 The SQL optimizer can't use an index on myDate, even if one exists. It will literally have to evaluate this function for every row of the table. Much better to use: WHERE myDat...