loveindia Posted June 2, 2016 Report Posted June 2, 2016 Just now, k2s said: antey endo seppochu kada man imp un-imp antey saripothunda endi daddy pillalni ala rape chestunnav.. is this good for a aged person like u man... Quote
loveindia Posted June 2, 2016 Report Posted June 2, 2016 1 minute ago, mtkr said: avi ekkado copy kotti raasukunnaviii... guruvu vinadaaniki idi chaala baagundi man.. keep it coming man... Quote
k2s Posted June 2, 2016 Report Posted June 2, 2016 Just now, loveindia said: endi daddy pillalni ala rape chestunnav.. is this good for a aged person like u man... Anxiety to know more man Quote
loveindia Posted June 2, 2016 Report Posted June 2, 2016 1 minute ago, k2s said: Anxiety to know more man ee age lo aa anxiety avasaramaa man... Quote
k2s Posted June 2, 2016 Report Posted June 2, 2016 8 minutes ago, loveindia said: ee age lo aa anxiety avasaramaa man... chaduvu ki prema / love / ishq ki vayasu tho emi sambandam man ? Quote
k2s Posted June 2, 2016 Report Posted June 2, 2016 34 minutes ago, k2s said: qochens sir 1) what is difference between Table/Index Scan vs Seek ? How SQL server evaluate(search row) in each case ? 2) Create Index on filtered, aggregated col, antey ela chestharu ? oka table lo index ni ela create chestharu ? 3) Join ki correlated sub query ki difference enti ? how does SQL server evaluate in each case ? why join is preferred ? @loveindia @mtkr help ?? Quote
sri_india Posted June 2, 2016 Report Posted June 2, 2016 10 minutes ago, loveindia said: ee age lo aa anxiety avasaramaa man... batch eppudu start chesthunaru guruji Quote
loveindia Posted June 2, 2016 Report Posted June 2, 2016 8 minutes ago, sri_india said: batch eppudu start chesthunaru guruji r u sishya or sishyuraalu man.. Quote
k2s Posted June 2, 2016 Report Posted June 2, 2016 8 minutes ago, loveindia said: r u sishya or sishyuraalu man.. y so gender biased man ? naaaledgy is wine noo.. pour it on everyone Quote
sri_india Posted June 2, 2016 Report Posted June 2, 2016 18 minutes ago, loveindia said: r u sishya or sishyuraalu man.. ippudu shisya antee no batch antavaaa ... shishya neee Quote
mtkr Posted June 2, 2016 Author Report Posted June 2, 2016 23 minutes ago, k2s said: qochens sir 1) what is difference between Table/Index Scan vs Seek ? How SQL server evaluate(search row) in each case ? 2) Create Index on filtered, aggregated col, antey ela chestharu ? oka table lo index ni ela create chestharu ? 3) Join ki correlated sub query ki difference enti ? how does SQL server evaluate in each case ? why join is preferred ? 1) Index scan is looking all data pages from first to last... index seek is looking specific data pages... scan preferred whn tbl is small.. seek preferred whn tbl is large... orders table having no index on it select * from orders --- table scan orders table having clustered index on it select * from orders --- index scan orders table having clustered index on it select * from orders where id = 2 --- index seek https://blogs.msdn.microsoft.com/craigfr/2006/06/26/scans-vs-seeks/ 2) create index index_name on table_name (column_name) 3) correlated sub query - its a subquery wch uses values from outer query for execution (frm ggle) A correlated subquery is one which uses values from the parent query. This kind of query tends to run row-by-row, once for each row returned by the outer query, and thus decreases SQL query performance. New developers are often caught structuring their queries in this way—because it’s usually the easy route. Here’s an example of a correlated subquery: SELECT c.Name, c.City, (SELECT CompanyName FROM Company WHERE ID = c.CompanyID) AS CompanyName FROM Customer c In particular, the problem is that the inner query (SELECT CompanyName…) is run for each row returned by the outer query (SELECT c.Name…). But why go over the Company again and again for every row processed by the outer query? A more efficient performance tuning technique would be to refactor the correlated subquery as a join: SELECT c.Name, c.City, co.CompanyName FROM Customer c LEFT JOIN Company co ON c.CompanyID = co.CompanyID In this case, we go over the Company table just once, at the start, and JOIN it with the Customer table. From then on, we can select the values we need (co.CompanyName) more efficiently. 1 Quote
sri_india Posted June 2, 2016 Report Posted June 2, 2016 indhulo disco chusthuntee urgent gaa SQL technologies ki shift ayipovali ani undi... chala support undi ee DB lo SQL tech ki Quote
sanbk Posted June 2, 2016 Report Posted June 2, 2016 Why can't you build non clustered indexes on all the columns provided you have good CPU performance (wipro interveiw question) SSIS vi post chestha next... Quote
ronitreddy Posted June 2, 2016 Report Posted June 2, 2016 54 minutes ago, k2s said: antey endo seppochu kada man imp un-imp antey saripothunda daddy..pillola mida ala satires veyocha? Quote
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