I haven't written anything for a long time. Recently, my company's projects are all in the early stage of development. I think I should write something for review. Otherwise, I won't be able to remember it all in the future. Two writing plans, one of which is Mercury's qtp. Although it has been used from 6.5 to the current 9.1, it has not been well organized. Vsts for testers started learning since the launch of vsts last year. It includes two major t
fast bitwise operations. Create a test table customer:Sql> CREATE TABLE Customer (customer# number,marital_status varchar2, Region VARCHAR2, gender varchar2 (10), Income_level VARCHAR2 (10));Table created.Insert 6 records using the following sql:Sql> INSERT into customer values (101, ' single ', ' East ', ' Male ', ' bracket_1 ');1 row created.Sql> INSERT into the customer values (102, ' married ', ' central ', ' female ', ' bracket_4 ');1 row created.Sql> INSERT into customer values (103, ' ma
GoogleSuspected Fraud in advertising plans
Google Since the launch of the advertising program, Chinese people are eager to make some foreign money. 05 Year 9 The month has been posted on my blog forum. Google Today, 4 Years have passed, and my blog traffic has exceeded 24 10 thousand, but please take a look at the money I make on the advertisement:
4 The amount obtained is less 9 USD, and must wait 50 USD or above, Google Th
data access strength and only filters data.In the predicate, pay attention to access. Consider the condition of the predicate and check whether the access path used is correct.
5. Dynamic AnalysisIf the following prompt appears in the execution plan:Note-------------Dynamic sampling used for the statementThis indicates the technology currently used by CBO, which needs to be taken into account in the analysis plan. When this prompt appears, it indicates that the current table uses dynamic sampli
much about what Http calls.With a few appeals, basic developers can switch from traditional development mode to cloud mode without feeling.Spring Boot + Cloud actually simplifies our development and improves efficiency. Let's focus more on the implementation of specific business functions.Real developers, don't feel the difficulty of switching from traditional mode to Cloud micro-service mode. When applied, you will find that everything has become simple and clear. If it is still the same, it c
First, create a power plan
1, the lower left corner of the desktop right click, and then in the pop-up menu below we click on the "Power Options" option to open into;
2, then we click on the power options below the "Create power Plan" to enter, as shown in the following figure;
3, then we can set up according to the requirements, the effect shown in the following figure;
4, the completion of the creation of the interface.
Second, delete the power Plan
1, since there is a creation
optimization | statement | execution
5th. Oracle's execution planbackground knowledge: To better carry out the following, we must understand some conceptual terms: Sharing SQL statementsIn order not to parse the same SQL statement repeatedly (because parsing operations cost resources, resulting in performance degradation), after the first parsing, Oracle stores SQL statements and parsed execution plans in memory. This memory in the shared buffer po
variables ALTER INDEX ix_c on _t REBUILD;GO SET showplan_all onGODECLARE @v varchar; SELECT * from _t WHERE c = @v; --varcharGO SET showplan_all OFF;GO ALTER INDEX ix_c on _t REBUILD;GO SET showplan_all onGODECLARE @nv nvarchar; SELECT * from _t WHERE c = @nv; --nvarcharGO SET showplan_all OFF;GOThe results for example are as seen in:Whether it is a varchar or a nvarchar variable, the estimated number of rows is 99.0099. This value is the same as the result of using the nvarchar constant va
, regardless of whether the specified value has only one data. The estimated results are all 99.0099, which indicates that the estimate does not take into account the values we specify.Further testing with variables ALTER INDEX ix_c on _t REBUILD;GO SET showplan_all onGODECLARE @v varchar;
SELECT * from _t WHERE c = @v; --varcharGO SET showplan_all OFF;GO ALTER INDEX ix_c on _t REBUILD;GO SET showplan_all onGODECLARE @nv nvarchar;
SELECT * from _t WHERE c = @nv; --nvarcharGO SET showpla
affect performance, 0 or 1 This identifies the status of the field because most of the data is the same index does not make any difference(Two indexes, 1 is a clustered index, 2 nonclustered indexes, a clustered index can have only one per table, a nonclustered index each table may have more than one, the primary key ID is a typical clustered index, the clustered index is similar to the dictionary lookup pinyin A, B, c ...) and the dictionary text content order is the same, the nonclustered ind
each step succeeds or fail, and finally select the step to begin with. In the Schedule tab, a maintenance plan that resembles a backup, filling out the scheduling cycle, which is the periodic cleanup cycle, is no longer detailed.If necessary, you can set the notification item after the job is completed on the last Notification tab, set up the operator, and set up the appropriate service, which is not specified here, usually not ... Originally are manually performed above the various operations,
defined, records in the table are displayed in the order in which they are entered. The primary key features: Uniqueness, non-nullability. Example of setting a primary KEY statement: Code int PRIMARY key, primary key cannot be empty, cannot be duplicated, ensures uniqueness Example of setting a self-growing primary KEY statement: The code int primary Key identity ( 1) starts at 1 each time , adding values you do not need to add this column To set a foreign key: Right-click on the table wh
(Dbms_xplan.display_cursor (null,0, ' allstats last '));The Dbms_xplan.display_cursor function is defined as:--Display from V$sql_plan (or V$sql_plan_statistics_all)function Display_cursor (sql_id varchar2 default NULL,Cursor_child_no integer default 0,Format varchar2 default ' typical ')Return dbms_xplan_type_tablepipelined;Where the parameter sql_id is the parent cursor, or NULL, indicates the SQL execution plan before the session is displayed. Cursor_child_no is the ordinal of a child cursor
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What kind of business plan is a good business plan? To impress venture capitalists? Zhou Hongyi, an angel fund investor, told you that the ten-page PPT is sufficient.
Once upon a time, the words venture capital, Vc, and burning money were everywhere. Who do not want to be able to get a venture capital and provide a booster for their startup career?To be favored by investors and obtain investment funds, a good business plan is an important first step.
How to write a business plan?
According to foreign media reports,Nokia's U.S. subsidiary said it plans to stop selling feature phones and Symbian smartphones in the United States and Canada and push for Windows Phone sales.
"When we launched a Windows Phone, we basically quit services such as Symbian and S40 ."
In an interview with AllThingsD, Chris Weber, president of Nokia's U.S. subsidiary, said the company will also focus on sales through traditional wireless carriers. In th
Obtaining execution plans and execution costs and writing the optimal SQL statements are required by each Oracle Developer and dba. Dbarole by default after Oracle11g
Obtaining execution plans and execution costs and writing the optimal SQL statements are required by each Oracle Developer and dba. After Oracle 11g, the default role is dba role.
Obtaining execution
http://www.scarydba.com/2011/06/15/rebind-and-rewind-in-execution-plans/Ever looked at an execution plan? If you answered no, you can ' t possibly has ever tried to tune a query, or, you ' re doing it wrong. For every one else, no doubt you ' ve looked at the tool tips or the property sheets of a operator and you ' ve seen the Rebi nd Rewind Properties and wondered what the heck they mean. Me too.I learned as much as I could for the book on execution
Document directory
Use setTimeout to delay function execution
Use clearTimeout to cancel an execution plan
Develop and cancel repeated execution plans for Functions
Use process. nextTick to delay function execution to the next round of the event Loop
Congestion event Loop
Exit event Loop
Use setTimeout instead of setInterval to ensure the serialization of function execution
For the list of articles in this series and the translation progres
1. OverviewRole: Used to maintain resource plans, resource usage groups, and resource plan directives, and package dbms_resource_manager_privs is used to maintain permissions related to resource management.2, the composition of the package1), Dbms_resource_manager.create_planRole: Establish a resource planSyntax: Dbms_resource_manager.create_plan (Plan in varchar2,comment with varchar2,cpu_mth in varchar2 default ' emphasis ',active_sess_pool_mth in v
plan, which greatly increases the period of optimization. If you do not want to execute the statement and just want to get an execution plan can take:Sql> Set Autotrace traceonlyThis will only list the execution plan and not the actual execution of the statement, greatly reducing the tuning time. Although statistics are also listed, this statistic is useless because there is no execution of the statement, and if you encounter an error when executing the statement, the workaround is:(1) Under th
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