MySQL equivalent of DECODE function in Oracle
You can use IF() where in Oracle you would have used DECODE().
You can use IF() where in Oracle you would have used DECODE().
This is a mix of the two previous answers:
Try this OR
If you want to be correct, use INFORMATION_SCHEMA. Alternatively, you can use SHOW TABLES If there is a row in the resultset, table exists.
IF you have tables A and B, both with colum C, here are the records, which are present in table A but not in B: To get all the differences with a single query, a full join must be used, like this: What you need to know in this case is, that when a record can be found in A, but not in B, … Read more
Sounds like they want the ability to return only allowed fields, which means the number of fields returned also has to be dynamic. This will work with 2 variables. Anything more than that will be getting confusing. Dynamic SQL will help with multiples. This examples is assuming atleast 1 column is true.
You could also try EXISTS: and per the documentation, you can SELECT anything. Traditionally, an EXISTS subquery starts with SELECT *, but it could begin with SELECT 5 or SELECT column1 or anything at all. MySQL ignores the SELECT list in such a subquery, so it makes no difference.
That syntax isn’t valid in Oracle. You can do this: Or you might be able to do this: It depends if the inline view is considered updateable by Oracle ( To be updatable for the second statement depends on some rules listed here ).
You’d need to make a User-Defined Function if you wanted to have syntax similar to your example, but could you do what you want to do, inline, fairly easily with a CASE statement, as the others have said. The UDF could be something like this: … and you would call it like so …
From the Oracle docs ROWID Pseudocolumn For each row in the database, the ROWID pseudocolumn returns the address of the row. Oracle Database rowid values contain information necessary to locate a row: The data object number of the object The data block in the datafile in which the row resides The position of the row … Read more