uberpool estimate

,Let's build this one. Index: CREATE index idx_col2_col3 on Teststatistics(col2,col3)Executes a query that is estimated to be 4127.86 rowsThen drop the index above and continue creating an index: Create index idx_col3_col2 on Teststatistics(col3,col2)Note that the order of COL2 and COL3 is inconsistentContinue execution of the above query (the query condition is unchanged, the data is unchanged, only the index column order has changed), this time is estimated to be 2414.91 row Query conditions,

How to estimate the test workload (1) conventional methods for estimating test workloadAs a manager, are you asked how long a project will take, how much human testing is required, or as a normal tester, are you asked how long it takes to complete a task or perform a regression test? I think most people in the software industry may have such questions about workload estimates. So how did you answer this question? Are you confident in your answers? Do

, COL3 DATETIME , COL4 VARCHAR ()GO INSERT into Teststatistics VALUES (RAND () *10,cast (GETDATE ()-rand () * 1000000 Problem Recurrence First look at a very interesting question, on the same table, first build an index: CREATE index idx_col2_col3 on Teststatistics(COL2,COL3) executes a query, estimated to be 4127.86 rows Then drop the index above and continue creating an index: Create index idx_col3_col2 on Teststatistics(col3,col2) Note that the orde

Give engineers a standard estimate of project time, engineers estimate the projectGive engineers a standard estimate of project time An experienced project manager who once worked with me claimed that after obtaining the programmer's time estimation, he first multiplied it by π and then converted it to the next time order of magnitude, to get the true value. 1 d

For individual stationmaster, generally do not need to estimate the keyword flow, as long as find the most appropriate keywords, directly to do can, how much to do how much, but to work in the Enterprise SEO, especially large companies, the entire SEO project can be recognized by the leadership, the application of budget, staff, work flow and time, All need SEO to provide a clear estimate of traffic and val

(i) Conventional methods of estimating the workload of the testAs a manager, are you asked how much time, how many human tests a project will take, or, as an ordinary tester, are you asked how much time is spent to complete a task or a regression test? I think most people in the software industry are more or less confronted with the question of workload estimation. So, what did you say? Do you have confidence in your own answer? Did you finally find that the actual time spent is quite different

Meet a good question. Now do a lot of wearable devices. I didn't write the corresponding program. But the principle is to understand some.Ask:1. Bind a 9-axis attitude sensor on the thigh2. According to the real-time data collected by the sensor to calculate the forward and backward side-shift squat and other actions, and can estimate the speed, can have errorsFor:Do you have so many axes? Only the three axes are known, the opposite direction is the d

Before doing the website, generally will make an estimate of the flow rate of the keyword. And usually used to do this reference value is the Baidu index. But the webmaster index webmaster will know that Baidu index with the actual flow of the difference is too far. Sometimes a word of tens of thousands of indices, the first is not 1000 of the flow. Baidu official also officially explained Baidu Index does not mean the search volume. and plus a variet

Ctr Pre-estimate method: FFM @ (calculated ads) [Calculated ads] CTR Pre-estimate method FFM 1FM 1 background 11 linear Model 122-item model 2 FM FM Fundamentals 22 data Analysis 23 parameter Count 24 compute time Complexity 25 gradient 26 Training time complexity 2FFM 1 background and Fundamentals 2 model and optimization problem 21 Model 22 Optimization Problem 23 Adaptive learning rate The final form of

-----The growth of the database in the last seven days, this is only an estimate. Select SUM (space_used_total)/1024/1024/1024 "Last 7 days DB increase-g" From Dba_hist_seg_stat S, Dba_hist_seg_stat_obj O, Dba_hist_snapshot SN where s.obj# = o.obj# and sn.snap_id = s.snap_id and Begin_interval_time > Sysdate-8 ORDER BY Begin_interval_time / The following additional two scripts are similar to the Web: Scripts: View database History growt

In the process of work, we often face a number of projects or a number of tasks, if not to clear the task, or do not put the time for scientific and reasonable assessment, it is easy to lead to time is not enough, the test is not sufficient, and then the leadership does not approve, his hard work not only not get the reward but the dilemma of pressure.What should we do?Talk about my own views, I hope you see more exchanges. Each tester's work has a large number of tasks, so it is necess

PremiseWhen this article discusses only SQL Server queries,For non-composite statistics, where the statistics for each field contain only the data distribution of theHow to estimate the number of rows based on statistical information when combining queries with multiple fields.The algorithm principle of estimating the number of data rows using statistics from different fields, and the differences between SQL Server 2012 and SQL Server 2014,For the tim

fond of them. For example: 1. To know how many lines of code can be completed (if you use the code line estimation ). Tip: no matter whether it is 1000 rows or not, the number of rows is 1000. Why should we estimate it in advance? (This is a question I was asked eight years ago) 2. In order to know how long it will take to complete and make a plan. TIPS: our plans are all reversed. How long will the leaders say, and how long will we do? What is the v

Estimate the index size before an Oracle index is created. Estimate the index size before a field in a table is created. The best way is to create an index in the test database for prediction. If no test is performed Estimate the index size before an Oracle index is created. Estimate the index size before a field in a

How to reasonably estimate the thread pool size?Although this problem seems small, it is not so easy to answer. If you have a better way to welcome us, let's start with a naïve estimation method: Assume that a system's TPS (Transaction per Second or task per Second) is required at least 20, and then assume that each Transaction is done by a single thread, Continue to assume that the average time for each thread to process a transaction is 4s. Then the

Why can't developers estimate time? Why can't developers estimate the time? We can't estimate the time for any individual task in software development because the nature of the work is creating new knowledge. In software development, we cannot estimate the time required for a single task, because the essence of work is

Suppose I go to a certain website every day, such as a pea pod that crawls a download of an app, and if it's a fixed time crawl every time, I'm sure I can catch every download. But I can not do a fixed time every day crawl, I can only do not fixed time to crawl once a day, how to use the algorithm to estimate the number of downloads a day. Reply content: Suppose I go to a certain website every day, such as a pea pod that crawls a download of an

-intensive areas are particularly severe. According to experience, the PV module will generate more than 10% of the power generated before the cleanup. In different regions, the average ash loss of different months, seasons or years can be summed up according to experience. It is very meaningful to accurately estimate power generation.b) Snow. The effect of snow on light irradiation in some areas will affect the power output of PV modules in specific

Before using compression, we can estimate the effect of compression.Dbms_comp_advisor can be used before 11gr2. The specific code is provided in the attachment. You only need to execute two files, dbmscomp. SQL and prvtcomp. plb, and then use the DBMS_COMP_ADVISOR.getratio stored procedure. It is not described in detail. SQL> set serveroutput onSQL> execdbms_comp_advisor.getratio('SH','SALES',10)Sampling table: SH.SALESSampling percentage: 10%Estimate

Estimate the index size (dbms_space.create_index_cost) before creating an index for a field in a table. The best way is to create an index in the test database for prediction.If no test environment is available, you can use dbms_space.create_index_cost to estimate its size. Syntax: www.2cto.com DBMS_SPACE.CREATE_INDEX_COST (ddl IN VARCHAR2, used_bytes out number, alloc_bytes out number, plan_table IN VARCHA