data-access-object

问题 Using Excel 2010, SQL and DAO I am trying to execute a query against tables which reside outside the current spreadsheet. This would be trivial, inside Access, with linked tables/databases, but using VBA in excel, I am stymied. Presuming these: ExcelFileOne; Tab; various headed field/columns ExcelFileTwo; Tab; various headed field/columns I want to execute a query inside a third excel file, that goes something like this [using dot notation for explanation, not coding....] -- a simple example:

问题 I am using play-slick for my scala Play! dummy rest API. So, I have to fetch records from multiple tables. But, they are interdependent, i.e. Table_1 Table_2 id1 id2 id2 To fetch a record from Table_2 I have to fetch a record from Table_1 and then using id2 fetch from Table_2. My controller: def getEntity(id : Long) = Action.async { table1DAO.findById(id) map { t1 => t1 map { t1Entity => table2DAO.findById(t1Entity.id2) map { t2 => t2 map { t2Entity => Ok(Json.toJson(CombiningClass(t1Entity,

问题 I am stymied by an SQL mediated import of a CSV file using VBA code. I am using a Third EXCEL macro/spreadsheet, to analyze a LEFT JOIN of 2 files, one as an XLXS and the other as a CSV. I suspect that part of the problem may be how the SQL command is used, for a FROM reference to an excel file. I am using Excel VBA, 2010, The 14 Database Access Engine. I want to end with an SQL statement that pulls from an external comma delimited CSV file I anticipate heading the macro with this pseudo code

问题 Having studied Java at school I am quite familiar with the DAO-pattern(Data access object). However at work I use .NET. In .NET there is often talk about the DAL(Data Access Layer). To me their purpose seems quite similar. So the question is are DAO and DAL basically the same thing? Is the term DAL only made up so it wouldn't be mixed up with Data Access Objects? 回答1: The Data Access Layer (DAL) is the layer of a system that exists between the business logic layer and the persistence /