I want to store a tree structure of arbitrary depth in an SQL database (MySQL, but want to avoid DBMS-specific features). Now I want to compute a value N for each node as follows:
I have the following query SELECT tagindex, AVG(val) from floatTable 开发者_StackOverflow社区 WHERE tagindex IN(828,856,883,910)
I am attempting to make some reports in Excel using a pivot table of a Sql server view. One of the customer requirements is to be able to filter the reports based on a date range they select, which se
I\'m struggling with applying the visitor pattern on some objects that have scalar members and at the same time aggregate members (collections).
I have a time series (zoo with index type chron) and I need to calculate cummax(mydata)-mydata on every day separately, in a new zoo object.
Say if there is a table with fields Products -------- ID CategoryID Name Price ... etc How can Ruby on Rails give a table that returns
Take a class which has relations with a couple of other classes. The first class can be seen as the aggregate(root). Seen from the point of the service layer how would one best split the calls?
I have an Oracle 10g table that contains a # of log records. This table collects data from an environmental recording device that creates a log record every 15 seconds when it is running.
Consider the following table: ID nonUniqueID value total -------------------------- 1123455x 21234510x 378920x
I have two table Company and Employee. And there relation is Company(one) -Employee(many). And I want to concatenate all the Employees\' name to a string and output.
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