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nvarchar和varchar相互转换、联合查询 - ORACLE - 清泛IT论坛，有思想、有深度
...atype is NVARCHAR2.
（A表字段c_xxx:varchar，B表c_xxx:nvarchar）
select translate(c_xxx USING NCHAR_CS) from A
union all
select c_xxx from B
或者
select c_xxx from A
union all
select translate(c_xxx USING CHAR_CS) from B
注意：translate函数括号中没有逗号。
1、...
Sequelize Unknown column '*.createdAt' in 'field list'
... do not contain a timestamp column.
When you do user.find it will just do SELECT user.*, which only takes the columns you actually have. But when you join, each column of the joined table will be aliased, which creates the following query:
SELECT `users`.*, `userDetails`.`userId` AS `userDetails.u...
Eclipse: The declared package does not match the expected package
...instead of src.
It may be easiest to right-click on the src directory and select "Build Path / Remove from build path", then find the src/prefix1 directory, right-click it and select "Build Path / Use as source folder".
sha...
How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
...
Android selector & text color
...or/button_dark_text.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true"
android:color="#000000" /> <!-- pressed -->
<item android:state_focused="true"
...
c# datatable to csv
...s = dt.Columns.Cast<DataColumn>().
Select(column => column.ColumnName).
ToArray();
sb.AppendLine(string.Join(",", columnNames));
foreach (DataRow row in dt.Rows)
{
string[] fields = row.ItemArray.Select(field => fie...
Linux: copy and create destination dir if it does not exist
...ersion of cp (and not, for instance, the Mac version), and
You are copying from some existing directory structure and you just need it recreated
then you can do this with the --parents flag of cp. From the info page (viewable at http://www.gnu.org/software/coreutils/manual/html_node/cp-invocation....
Change R default library path using .libPaths in Rprofile.site fails to work
...ite settings or perhaps is overriding them by reading an .Rprofile setting from one of the RStudio defaults. It should also be mentioned that the result from this operation also appends the contents of calls to .Library and .Library.site, which is further reason why an RStudio- (or any other IDE or ...
Make a program run slowly
...ux scheduler will have this issue. There was some sort of thread analyzer from Intel afair. I see Vtune Release Notes. This is Vtune, but I was pretty sure there is another tool to analyze thread races. See: Intel Thread Checker, which can check for some thread race conditions. But we don't kno...
How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
... @sweisgerber.dev, I'm confused on your first contention. The return value from find will only be zero if titi is at the start of the string. If it's found somewhere else, you'll get a non-zero return value and, if it's not found, you'll get npos which is also non-zero. Assuming I'm right, I'd prefe...