There is no default value for a CAST: A type cast specifies a conversion from one data type to another. PostgreSQL accepts two equivalent syntaxes for type casts: CAST ( expression AS type ) expression::type There is no room in the syntax for anything other than the expression to be casted and the desired target … Read more
To answer your question, yes, it will only run a single match and then break. However, if you’d like to have logic to allow for conditional matching in the update, the CASE statement is rather useful for this. Something like this as an example: MERGE INTO YourTable USING (VALUES (1, 1, NULL), (0, 0, NULL), … Read more
Will OPTION(OPTIMIZE FOR UNKNOWN) reuse cache instead of recompiling each time? Yes, it will. There are two main differences between OPTION(OPTIMIZE FOR UNKNOWN) and OPTION(RECOMPILE) as can be seen from this quote from MSDN: OPTIMIZE FOR UNKNOWN Instructs the query optimizer to use statistical data instead of the initial values for all local variables when … Read more
Use SCOPE_IDENTITY: — do insert SELECT SCOPE_IDENTITY(); Which will give you: The last identity value inserted into an identity column in the same scope. A scope is a module: a stored procedure, trigger, function, or batch. Therefore, two statements are in the same scope if they are in the same stored procedure, function, or batch.
You can use case expression: ORDER BY CASE WHEN Column1 IS NOT NULL THEN Column1 ELSE Column2 END Or the corresponding syntactic sugar: ORDER BY COALESCE(Column1, Column2) The result will be like: column1 | column2 ——–|——– 1 | 1258 2 | 5972 null | 3 4 | 3698 5 | 7524 Note that the datatype … Read more
In DataGrip, as in other IntelliJ-based IDEs, everything is about source editing. What you want can be achieved this way: Open console Start typing sel, you’ll get completion popup (if not, hit Ctrl+Space) Choose sel here, which is live template for SELECT statement SELECT statement will be generated, asking for table name and column list … Read more
Late answer… You can use CAST or CONVERT thus CAST(foo AS CHAR(100)) CONVERT(foo, CHAR(100)) Supported types (5.5) are: BINARY[(N)] CHAR[(N)] DATE DATETIME DECIMAL[(M[,D])] SIGNED [INTEGER] TIME UNSIGNED [INTEGER] You can not cast to varchar directly. There is an open MySQL bug from 2008 which no-one seems to care about and is damn annoying
[Expanding on dvv’s answer] You can move to an existing table as follows. For unmatched schema, you should specify columns. WITH moved_rows AS ( DELETE FROM <original_table> a USING <other_table> b WHERE <condition> RETURNING a.* — or specify columns ) INSERT INTO <existing_table> –specify columns if necessary SELECT [DISTINCT] * FROM moved_rows; But you want … Read more
The best way is to make sure that you run SELECT COUNT on a single column (SELECT COUNT(*) is slower) – but SELECT COUNT will always be the fastest way to get a count of things (the database optimizes the query internally). If you check out the comments below, you can see arguments for why … Read more