field

问题 How would I get the number of fields/entries in a database using an SQL Statement? 回答1: mmm all the fields in all the tables? assuming standards (mssql, mysql, postgres) you can issue a query over information_schema.columns SELECT COUNT(*) FROM INFORMATION_SCHEMA.COLUMNS Or grouped by table: SELECT TABLE_NAME, COUNT(*) FROM INFORMATION_SCHEMA.COLUMNS GROUP BY TABLE_NAME If multiple schemas has the same table name in the same DB, you MUST include schema name as well (i.e: dbo.Books, user.Books

问题 I've got a weak imagination when it comes to names, so I often find myself re-using identifiers in my code. This caused me to run into this specific problem. Here's some example code: public delegate void TestDelegate(int test); public class Test { private int test; private void method(int aaa) { TestDelegate del = test => aaa++; test++; } public static void Main() { } } Here are the compilation errors (output by ideone): prog.cs(11,3): error CS0135: `test' conflicts with a declaration in a

问题 I have some models; Vocabularies (tags lists), Labels (tags) and different articles types. These article types have some vocabs enabled, and some not, for instance: Image can tagged with terms from A, B and a news article with terms from A or C. This however only exists at the database level. What i'm trying to do is to output fields depending on if a vocab is enabled for a content type or not, like this: Determine if this content type is connected to a vocabulary. Load the vocabularies

问题 (This is a related question, but there are difference with my case that makes me doubt my understanding of it). I have this class: class MyOwnClass { public: int score; Specialcustomtype val1; double index; private: }; and a vector of MyOwnClass vector<MyOwnClass> MySuperVector(20); Having some code that set values to the fields of MyOwnClass, I want to find which MyOwnClass in the vector has the field score with the highest value. In an answer from the related questions : #include <algorithm

问题 I'm tying to hide my slug fields in the admin by setting editable=False but every time I do that I get the following error: KeyError at /admin/website/program/6/ Key 'slug' not found in Form Request Method: GET Request URL: http://localhost:8000/admin/website/program/6/ Exception Type: KeyError Exception Value: Key 'slug' not found in Form Exception Location: c:\Python26\lib\site-packages\django\forms\forms.py in __getitem__, line 105 Python Executable: c:\Python26\python.exe Python Version:

问题 I'm wondering if it is possible to override the default value of a field when it is returned. Say I had a model: class ModelA(models.Model) name = models.CharField(max_length=30) Is there any way that calling modela_instance.name can return a modified value, for example name + " foo", but have the code that appends foo run by default within the model itself, so all I would need to do is call name to get the appended value? I should elaborate and say that what I'm actually hoping to do is have

问题 I'm wondering if it is possible to override the default value of a field when it is returned. Say I had a model: class ModelA(models.Model) name = models.CharField(max_length=30) Is there any way that calling modela_instance.name can return a modified value, for example name + " foo", but have the code that appends foo run by default within the model itself, so all I would need to do is call name to get the appended value? I should elaborate and say that what I'm actually hoping to do is have

问题 I'm constructing a method to take in an ArrayList(presumably full of objects) and then list all the fields(and their values) for each object in the ArrayList. Currently my code is as follows: public static void ListArrayListMembers(ArrayList list) { foreach (Object obj in list) { Type type = obj.GetType(); string field = type.GetFields().ToString(); Console.WriteLine(field); } } Of course, I understand the immediate issue with this code: if it worked it'd only print one field per object in

问题 I have a text file produced by some commercial software, looking like below. It consists in brackets delimited sections, each of which counts several million elements but the exact value changes from one case to another. (1 2 3 ... ) (11 22 33 ... ) (111 222 333 ... ) I need to achieve an output like: 1; 11; 111 2; 22; 222 3; 33; 333 ... ... ... I found a complicated way that is: perform sed operations to get 1 2 3 ... # 11 22 33 ... # 111 222 333 ... use awk as follows to split my file in

问题 ExtJS4 grid anticipates appropriate editor (cellEditor or rowEditor) per column. If a column's header field is dateField - date selector will be applied on every row in that column. What I need is an editor with different field editors per row, not per column. The Extjs3 solution is provided here - unfortunately doesn't fit in Extjs4 case. (please check that link to see explanatory images, cause I can't post images yet) There's also a single column solution called property grid, but again -