inspiron 5378

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　　HP 15-R221TX HP 15-R221TX is equipped with Intel Core i5 5200U processor, the main frequency 2.2GHz, the most Gao 2.7GHz, with 4GB memory and Nvidia GeForce 820M Independent graphics card, easy to play mainstream AV entertainment. 　　The more The Dell Inspiron 15 5000 The Dell Inspiron 15 5000 is equipped with the Intel Core i5 5200U processor, the main frequency 2.2GHz, the most Gao 2.7GHz, Web pa

14. In addition, the screen's black level, shadow detail, and maximum brightness (310 lux) are maintained at a good level. With the help of these parameters and matte coating, the E5 can be used normally even under the sun. However, this screen has a bit of a difference in color accuracy, and the average delta error we've measured is 9, and some colors even reach 10. As long as the error value is higher than 1, the naked eye can detect, so the E5 defect is still very obvious. In ac

next PageRank vectors by Qcur and Qnext respectively. The process is to compute the iterative powering for finding the first eigenvector. The computation ends until for some smallε (10-10).Inputthe input contains many test cases.For each case, there is multiple lines. The first line contains an integer N (nOutputoutput one line with the eigenvector. The numbers should is separated by a space and is correctly rounded to the decimal places.Sample Input40111001100010100Sample Out

test 100W data, the cost plan is the same.*********************************************3. The function operation does not satisfy the Sarg form, causes the index to be unable to use the example: the following SQL condition statement has the proper index in the column, but the execution speed is very slow:SELECT * FROM record where substring (card_no,1,4) =′5378′ (13 seconds) select * from record where amount/30Analysis:Any action on a column in the W

time. However, if an access plan is established at compile time, the value of the variable is still unknown and therefore cannot be selected as an input for the index. The following statement will perform a full table scan:SelectId fromTwhereYou can force the query to use the index instead:SelectId fromT with (index name)where 　　 7. Should try to avoidwhereclause, which causes the engine to discard the use of the index for full-table scanning. such as: SELECT* FROM T1 WHERE f1/2= -should read:

have the appropriate index, but the speed is very slow: SELECT * FROM Record wheresubstring (card_no,1,4) = ' 5378 ' (13 seconds)

indexes, but the execution speed is very slow: SELECT * FROM record where SUBSTRING (card_no,1,4) = ' 5378 ' (13 seconds) SELECT * FROM record where amount/30SELECT * FROM record where Convert (char, date,112) = ' 19991201 ' (10 seconds) ----Analysis: The result of any operation of the column in the----WHERE clause is computed by column in SQL Runtime, so it has to Do a table search without using the index above the column; If the results are availab

Label:The first palm avoids the action on the columnAny action on a column can result in a full table scan, where the so-called operations include database functions, calculation expressions, and so on, to move the operation to the right of the equation whenever possible, or even to remove the function.Example 1: The columns in the following SQL conditional statements are properly indexed, but the execution speed is very slow in the case of 300,000 rows of data:SELECT * FROM record where SUBSTRB

Label:Any action on a column can result in a full table scan, where the so-called operations include database functions, calculation expressions, and so on, to move the operation to the right of the equation whenever possible.Even remove the function.Example 1: The columns in the following SQL conditional statements are properly indexed, but the execution speed is very slow in the case of 300,000 rows of data:SELECT * from record where substrb (cardno,1,4) = '

)SELECT * from T1 WHERE ID >299999 and ID It is clear from the execution plan that the last method is used instead of the previous two ways of querying.That's what the internet says, but you do the test 100W data, the cost plan is the same.*********************************************3. The function operation does not satisfy the Sarg form, causes the index to be unusableExample: The columns in the following SQL conditional statements are indexed appropriately, but are very slow to execute:SELEC

, and varbinary are incompatible. Data Type incompatibility may make the optimizer unable to perform some optimization operations that can be performed originally. For example: Select name from employee where salary>60000 In this statement, if the salary field is of the money type, it is difficult for the optimizer to optimize it because 60000 is an integer. We should convert the integer type into a coin type during programming, instead of waiting for the conversion at runtime. 3. Avoid

finds the best solution for the least cost of the system, based on the join conditions, before the multiple table operations are actually executed. The join condition takes into account the table with the index, the table with many rows, and the selection of the inner and outer tables can be determined by the formula: the number of matches in the outer table * The count of each lookup in the inner-layer table, and the product minimum is the best scheme. ----2. View the method of executing a sc

record where SUBSTRING (card_no,1,4) = ' 5378 ' (13 seconds) SELECT * FROM record where amount/30SELECT * FROM record where Convert (char, date,112) = ' 19991201 ' (10 seconds) ----Analysis: The result of any operation of the column in the----WHERE clause is computed by column in SQL Runtime, so it has to Do a table search without using the index above the column; If the results are available when the query is compiled, Can be optimized by the SQL op

connection condition. ----Summary: ----1. The query optimizer lists several sets of possible connectivity scenarios and finds the best solution for the least cost of the system, based on the join conditions, before the multiple table operations are actually executed. The join condition takes into account the table with the index, the table with many rows, and the selection of the inner and outer tables can be determined by the formula: the number of matches in the outer table * The count of e