How to retrieve an average from a specific data type from a column in sql -

-

i have table called products, contains 2 rows (plus others):price , mfr. how list average price items provided particular manufacturer (using summary query)?

select avg(price) priceaverage products mfr = 'particularmanufacter'

but future recommend homework yourself. student :)


Comments

Post a Comment

Popular posts from this blog

delphi - TJvHidDeviceController "DevicePath" always showing "\" -

-
i'm using tjvhiddevicecontroller class retrive hid device information. have plugged 2 hid devices, i'm trying ge "devicepath" of sp_device_interface_detail_data_a structure getting device path '\'. ican't open createfile function. please me solve issue. os win7. all. this guessing! the 1 thing can think of is: tjvhiddevicecontroller calls windows api call without using or w suffix. structure used sp_device_interface_detail_data_a, ansi version. now, if use delphi 2009 or higher, routine expect sp_device_interface_detail_data_w. size same looks ok. strings stored usc2 encoded (widechars) instead of ansi encoded -> after every ansi character there null byte. tjvhiddevicecontroller converts character array pascal string using function strpas , hence, see first character. check: set breakpoint after function call fills structure , use cpu window view content memory dump. if see ansi characters every other byte , null bytes in between, ca...
Read more

java - where to store the user credentials in an enterprise application(EAI)? -

-
Image
background/context we developing event notification service . application @ high level looks below: our developene scope involves widget , ens. " ens " acts central point of collection types of events of interest users. user wants know when these types of events occur registers ens, identifies events in order , matches notifications subscriptions. the user wants subscibe should valid user of intergrated application(db, sap system etc) the sequence of events: now question is: what best pracitces in storing users db, sap etc credentials. edit how should user authenticated? should everytime messages delivered?(as @duffymo mentioned, if use strategy, affect source system) additional info: ens web-services. ens polls sap(and other applications) , problem becoming more complex. in sap there data-level authorization. not users allowed see events/data. if sap has pushed data, along user info has authorized see, no issues @ all. case 1: scheduler init...
Read more

java - netbeans "Please wait - classpath scanning in progress..." -

-
when try compile netbeans projects message/error : "please wait - classpath scanning in progress..." and nothing happens , have have wait enternity conmpile "hello world"... now first thing have moved new office building, laptop same. it's secure enviroment lot of "security", can't connect anywhere almost. have changed user dir in netbeans.conf save data in c:\program files\user any ideas how fix this? alrady tried reinstalling netbeans, changing save location between standart , newone... just ideas find problem look @ cpu - netbeans busy (100% on 1 core) or blocking (95% idle)? standard, ant or maven build? libraries , use absolute or relative paths? start simple "hello world" project (no dependencies), add 1 lib (log4j or similiar), located in project folder , - if works - move lib other locations (choose locations similiar libs on real classpath) there chance, don't have access rights folders/shares conta...
Read more