Question

I’m using java, eclipse, and JDBC.

I have 3 tables (company, priceVolume, dividend), of which priceVolume contains a string called transdate (the date of a stocks value split into several different categories, IE. openValue, CloseValue, averageValue…). In all of my tables, the primary key is Ticker (the stock ticker for a company).

I also have a attribute in company called Industry, which tells me what industry a stock comes from.

I have a span of days, for example 09.25.2001 to 02.28.2012 for one of them, which I want to get the values from priceVolume if the company is in the selected Industry.

I have this Query, and I don’t know how to phrase to WHERE clause to give me this span and only this span. If the type was a date type, I think I’d know how to phrase it. Currently however, as a string, I have no idea. I also have no control over the database, just reading from it.

ResultSet rsTickers = stat.executeQuery("SELECT Ticker, OpenValue, CloseValue,
TransDate FROM company NATURAL JOIN pricevolume WHERE industry = " + GivenIndustry + "
GROUP BY ticker");

I currently have my program set up so that it just gives me all of rows who’s industry matches the given industry and I just sort through them in my program (I throw out all of the one’s who aren’t in the span). It works, but I feel it’s really ineffective. So now I want to limit my Query to just the transDates which fit my criteria.

And I just want to see how to do it better.

Answer 1

You can cast to datetime and check like this

ResultSet rsTickers = stat.executeQuery("SELECT Ticker, OpenValue, CloseValue,
TransDate FROM company NATURAL JOIN pricevolume WHERE industry = " + GivenIndustry + "
AND CAST(transDates AS DATETIME) BETWEEN '2001-9-25' AND '2012-2-28' 
GROUP BY ticker");