sql - Using sum(), count(), and "group by" in Berkeley DB -

-

how use sum(), count(), , group by in berkeley db? there alternative way?

which api using? if you're using key/value api, need implement functions yourself, scanning database using cursor. if using sql api, can "select sum(), count() ... group ..." sql statement.

you may want post questions berkeley db forum.


Comments

Post a Comment

Popular posts from this blog

razor - Is this a bug in WebMatrix PageData? -

-
i think may have found bug in webmatrix's pagedata, not sure. concerns how pass data partial page calling page. in webmatrix documentation (tutorials, e.g. " 3 - creating consistent look ", , example code), pagedata recommended mechanism pass data between pages (e.g. content page layout page, or partial page). however have found not work other way, pass data partial page calling page. modifying or adding entries in pagedata in partial page, not seem calling page. cutting right down simplest possible example, in test page may have this: @{ pagedata["test"] = "initial entry"; } <p>before calling partial page, test value @pagedata["test"]</p> @renderpage("_testpartial.cshtml") <p>after returning calling page, test value @pagedata["test"]</p> and in _testpartial.cshtml page might have this: @{ pagedata["test"] = "modified entry"; } <p>in partial page...
Read more

iphone - Requiring the presence of a method in an id -

-
the situation my custom controller class has following method: - (void)requestviewcontrollerwithidentifier:(nsstring *)identifier fromobject:(id)object; this causes object receive message: - (uiviewcontroller *)viewcontrollerwithidentifier:(nsstring *)identifier; the problem right now, object id there's no guarantee implements method, , compiler warning when send message. the solution i came 2 solutions myself: use protocol. make id nsobject , create category nsobject . they both fine solutions , don't mind choosing 1 of them, but... the question ...i noticed apple doing odd in gamekit api. gksession has following method: - (void)setdatareceivehandler:(id)handler withcontext:(void *)context handler id , apple requires implement method: - (void) receivedata:(nsdata *)data frompeer:(nsstring *)peer insession: (gksession *)session context:(void *)context; without making use of protocol or category! i'm wondering how , why thi...
Read more

xslt - Is it possible to select a node that just includes a subset of the child nodes? -

-
i have xpath: //tbody/tr[2]/td/div/table/tbody/tr[2]/td[position() > 1] which gives me first child node. however, gives me nodelist of td notes result. want select parent tr node, first child td node removed. is possible using xpath? xpath query language xml documents. such cannot modify structure source xml document or create new xml document. the task of creating new, modified document cannot done xpath only. this easy accomplish xslt : <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/xsl/transform" xmlns:xs="http://www.w3.org/2001/xmlschema"> <xsl:output omit-xml-declaration="yes" indent="yes"/> <xsl:strip-space elements="*"/> <xsl:template match="node()|@*"> <xsl:copy> <xsl:apply-templates select="node()|@*"/> </xsl:copy> </xsl:template> <xsl:template match="tr[2]/td[1]"/> </xsl:...
Read more