Master HaKu

摘要： SQL在不同数据库中查询前几条记录的用法分类1. orACLE Select * FROM TABLE1 Where ROWNUM<=N 2. INFORMIX Select FIRST N * FROM TABLE1 3. DB2 Select * ROW_NUMBER() OVER(ORDER BY COL1 DESC) AS ROWNUM Where ROWNUM<=N 或者Select COLUMN FROM TABLE FETCH FIRST N ROWS ONLY4. SQL SERVER Select TOP N * FROM TABLE1 5. SYBASE SET 阅读全文

摘要： 通过如下sql语句SELECTcol_description(a.attrelid,a.attnum)ascomment,format_type(a.atttypid,a.atttypmod)astype,a.attnameasname,a.attnotnullasnotnullFROMpg_classasc,pg_attributeasawherec.relname='tablename'anda.attrelid=c.oidanda.attnum>0 阅读全文

摘要： 1. 将Postgresql的bin目录加入你环境变量的path路径2. psql -U postgres -c "CREATE DATABASE postgis_sample OWNER postgres TEMPLATE template_postgis ENCODING 'UTF8';" postgis_sample是你的数据库名字3. psql -d postgis_sample -U postgres -f D:\PostDbBak\SharpMap\postgisdemodb.backup postgisdemodb.backup是bak文件 阅读全文

摘要： 两个错误：1. Run-Time Check Failure #0 - The value of ESP was not properly saved across afunction call. This is usually a result of calling a function declared with onecalling convention with a function pointer declared with a different calling convention 先把dll的项目属性中C/C++->Code Generation->Basic Ru 阅读全文

摘要： 1. 首先，在Visual Studio中，我们建立一个Visual C++的项目 类型选择Win32 Project,继续选择Dll类型 该项目取名叫做myDll 1) 添加myDll.h头文件，代码如下：#ifdefA_EXPORTS#defineDLL_API__declspec(dllexport)#else#defineDLL_API__declspec(dllimport)#endifextern"C"DLL_APIvoidHelloWorld(); 这里HelloWorld()就是等下我们要暴露给C#调用的C方法。 注意：必须给函数增加extern " 阅读全文

摘要： The value of ESP was not properly saved across a function call. This is usually a result of calling a function declared with one calling convention with a function pointer declared with a different calling convention.解决方法：1. VC6 工程->设置->C/C++->工程选项 直接把 /GZ 给去掉2. VC.NET 项目属性->C/C++->代码 阅读全文

摘要： The netCDF library is implemented as a Windows dynamic link library (DLL).To install a DLL, you just have to leave it in some directory, and (possibly) tell yourcompiler in which directory to look for it.Similarly, you will need to put the header file, netcdf.h, somewhere that you compilercan find i 阅读全文

摘要： 1. What Is netCDF? NetCDF (network Common Data Form) 是一种跨平台的用于描述科学数据的格式。 目前可支持的语言版本有(Java, C/C++, Fortran)2. How do I convert netCDF data to ASCII or text? 参考 http://www.unidata.ucar.edu/software/netcdf/docs/ncdump-man-1.html 3. NetCDF的后缀名 ".nc" （ The recommended extension for netCDF files 阅读全文

摘要： 东西半球的坐标范围是-180到180负坐标代表西半球，正坐标代表东半球伦敦位于东西半球的交界，所以伦敦的横坐标是0南北半球的坐标范围是-90到90负坐标代表南半球，正坐标代表北半球 阅读全文

摘要： 1. 首先创建一个多边形的表CREATETABLEshp_polygon(polygon_idserialNOTNULL,"name"charactervarying(40),CONSTRAINTpk_shp_polygonPRIMARYKEY(polygon_id)USINGINDEXTABLESPACEpg_default)WITH(OIDS=FALSE)TABLESPACEpg_default;2. 使用Postgresql自带的“AddGeometryColumn”函数增加图形关系AddGeometryColumn会自动为你所要的表增加一个代表坐标点的数据列，名为： 阅读全文