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Oracle Differences between NVL and Coalesce
...guments to be of same datatype.
COALESCE gives issues in queries which use UNION clauses. Example
below
COALESCE is ANSI standard where as NVL is Oracle specific.
Examples for the third case. Other cases are simple.
select nvl('abc',10) from dual; would work as NVL will do an implicit conversion ...
MySQL LIKE IN()?
...CT *
FROM fiberbox f
JOIN (
SELECT '%1740%' AS cond
UNION ALL
SELECT '%1938%' AS cond
UNION ALL
SELECT '%1940%' AS cond
) с
ON f.fiberBox LIKE cond
This, however, can return you multiple rows for a fiberbox that is something like '1740, ...
How to change identity column values programmatically?
...ARY KEY,
X VARCHAR(10)
)
INSERT INTO Test
OUTPUT INSERTED.*
SELECT 'Foo' UNION ALL
SELECT 'Bar' UNION ALL
SELECT 'Baz'
Then you can do
/*Define table with same structure but no IDENTITY*/
CREATE TABLE Temp
(
ID INT PRIMARY KEY,
X VARCHAR(10)
)
/*Switch table metadata to new structure*/
ALTER T...
Simplest way to do a recursive self-join?
...nes the ultimate ancestors in your chain, change it as appropriate
UNION ALL
SELECT m.*
FROM mytable m
JOIN q
ON m.parentID = q.PersonID
)
SELECT *
FROM q
By adding the ordering condition, you can preserve the tree order:
WITH q A...
FIND_IN_SET() vs IN()
... name
FROM orders
CROSS JOIN
(
SELECT 1 AS pos
UNION ALL
SELECT 2 AS pos
UNION ALL
SELECT 3 AS pos
UNION ALL
SELECT 4 AS pos
UNION ALL
SELECT 5 AS pos
) q
JOIN company
ON companyID = CAST(NULLIF(S...
SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
...
This is wrong. FULL JOIN ON rows are INNER JOIN ON rows UNION ALL unmatched left table rows null-extended UNION ALL unmatched right table rows null-extended. So FULL JOIN can return M*N rows--possibly greater than both MAX(M,N) & M+N. But anyway the min & max number of row...
When to use Common Table Expression (CTE)
... ,null AS Answer
,1 AS Is_Question
FROM [Questions]
UNION ALL
SELECT Q.[Quiz_ID]
,[Question_ID]
,A.[ID] AS Answer_Id
,Q.Question_Text
,[Answer]
,0 AS Is_Question
FROM [Answers] A INNER JOIN [Questions] Q ON Q.Quiz_ID = A.Quiz...
Pandas groupby: How to get a union of strings
I have a dataframe like this:
8 Answers
8
...
What is in your Mathematica tool bag? [closed]
...n their original order, so if you set h = #1& then you get an unsorted Union, like in the examples for Reap. But, it can be used for secondary processing.
As an example of its utility, I've been working with Wannier90 which outputs the spatially dependent Hamiltonian into a file where each lin...
nvarchar和varchar相互转换、联合查询 - ORACLE - 清泛IT论坛，有思想、有深度
...帖最后由 zqp2013 于 2015-2-27 16:42 编辑
场景：联合查询（union all）Oracle两张表，同一组字段的数据类型不一致，分别是nvarchar和varchar。
这时联合查询报错如下：ora12704：字符集不匹配。
解决方法：需要对数据类型进行转换。
...