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,table2 b where a.id=b.idb:select * from Table1 Cross Join Table2 wheRe Table1.id=table2.id (note: After cross join conditions can only be used where, cannot be used on) three, crossed connections (full) 1. Concept: A cross join without a WHERE clause will produce a Cartesian product of the table involved in the join. The number of rows in the first table multiplied by the number of rows in the second table equals the size of the Cartesian product result set. (Table1 and table2 cross-joins gener

Tags: relationship DB2 problem complete ble run SQL very saveDatabase features: Mass storage, fast lookup, concurrency problem control, security, data integrity (the data stored in the database is correct, real).Table: [Relationships] in a relational database are tables. Different brands of DBMS have their own different features: MySQL (fast, suitable for the data requirements are not very rigorous place, removed many small and medium-sized enterprises infrequently used features),MSSQLServer (an

SqlException BEGIN--ERROR set p_return_code = 1; Rollback END; DECLARE exit handler for SQLWarning BEGIN--WARNING set p_return_code = 2; Rollback END; START TRANSACTION; DELETE from TB1; #执行失败 INSERT INTO blog (name,sub_time) VALUES (' yyy ', now ()); COMMIT; --SUCCESS Set P_return_cOde = 0; #0代表执行成功END//delimiter; #在mysql中调用存储过程set @res =123;call P5 (@res); select @res; Call stored procedure Cursor.callproc (' P5 ', (123,)) print (Cursor.fetchall ()) #查询s

MySQL Time function--Get Current dateSelectcurrent_date ();--Get current TimeSelectcurrent_time ();--gets the current date and timeSelectNow ();--get datetime year, month, daySelectYear (now ());--yearsSelectMonth (now ());--MonthSelectDay (now ());--days--returns the date portion of a datetimeSelectDate (now ());--Add date or time to datetimeSelectDate_add (now (), interval1Day);--the day after the current datetimeSelectDate_add (now (), Interval-1Day);--the day before the current datetimeSelec

specified fractional number before or after it, and it is truncated altogether.Its specific syntax format is as followsTRUNC (Number[,decimals])whichNumber to be intercepted and processedDecimals indicates the number of digits after the decimal point to be retained. Optional, ignore it to truncate all the decimal partsHere's how this function is used:TRUNC (89.985,2) =89.98TRUNC (89.985) =89TRUNC (89.985,-1) =80Note: The second parameter can be a negative number, which means that the portion of

sets of memory datax/8i 0x0804843b # Show 8-line Assembly instructions13. Processes and Threadsinfo proc Mappings # equivalent to cat/proc/{pid}/maps viewing maps memory databreakpoints can be set at pthread_create, which generates a hint when the thread is created. [New Thread 0xb7e78b70 (LWP 2933)]Info Threads # View All Threads listwhere # shows the current thread call stackThread num # toggle thread [Switching to thread 1 (thread 0xb7e796c0 (LWP 2932)] #0 0xb7fe2430 in __kernel_vsyscall ()1

MYSQLBMysql-uroot-p ' Mnvq_yog9 ' 5) Generate the Change master statement and execute it on the MYSQLB> STOP SLAVE; > Change MASTER to master_host= ' 172.16.4.235 ', master_user= ' repl_user ', master_password= ' mnvq_yog9 ', Master_log_ File= ' mysql-bin.000002 ', master_log_pos=120;> START slave;> SHOW SLAVE status\g650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M01/57/8A/wKioL1SdKKrCngloAATkjRsqgnM327.jpg "title=" 2.png " alt= "Wkiol1sdkkrcngloaatkjrsqgnm327.jpg"/>The status of Slave

directory of root super UserLib 32-bit library fileLIB64 64-bit library fileOpt third-party software installation addressUser Software Installation Addressvar frequently transformed data holds address log storage addressThe mount point of the MNT deviceLost+found didn't have time to save the file, the last strawIv. Catalogue of Proc Proc/cpuinfo CPU InformationCat/proc/cpuinfoLscpu Proc/meminof Memory InformationCat/proc/meminofFree-h: Human Readable language Proc/mounts Mounti

The previous Process Control 2, describes the zombie process, and the solution of the two kinds of 4. Add two more below.How to resolve:3: Ignore SIGCHLD signalParent process settings Ignore SIGCHLD signal, child process end automatically frees process table resourceIgnore SIGCHLD signal:Signal (SIGCHLD, sig_ign)4: Capture SIGCHLD SignalThe parent process captures the SIGCHLD signal and executes the wait () in the Capture function codeHandling SIGCHLD Signals:void Pfun (int nsignal)Signal (Sigch

In my previous blog on SQL logic query parsing, this article describes in detail the steps of SQL logic Query Processing and some important knowledge about the SQL language. For the integrity of SQL logic query processing, we will learn more about SQL logic Query Processing in this article as a supplement to the previous blog. Including table operators (JOIN, APPLY In my previous blog on SQL logic query parsing, this article describes in detail the st

Cross-site crawling of other sites to supplement the page, capture site pages. How to supplement the page capture of other sites across sites, capture site pages in practical applications, often encounter some special circumstances, such as the need for news, weather forecasts, and so on, however, how does one supplement the page capture of other sites and captur

CopyCodeThe Code is as follows :#! /Usr/bin/perl # # Use grep map to obtain the Intersection Set and supplement set of the two lists # Use strict; My @ A = ("A", "B", "C", "D", "E "); My @ B = ("B", "g", "F", "E "); Print "list a data: @ A \ n "; Print "List B data: @ B \ n "; My % A = map {$ _ => 1} @; My % B = map {$ _ => 1} @ B; My @ C = map {$ _ => 1} @ A; #=> the operator plays the role of hash assignment. # @ A @ B Intersection My @

complete, does not have the massive keyword and the long tail keyword rank guarantee, again good website also few people know. After all, our site through search engines can be indirectly displayed in front of the user. As shown in Figure 1. 　　 "Figure 1" Figure 1 is the weight of a hospital query, you can very clearly see that the station keyword in Baidu has a better ranking of about 2,413. Let's think about how many potential users of such a site will enter the station through

subsystem module sends the results of SQL execution to the client, and if it does not go well, send an error message. Finally, the server returns control to the connection thread, the connection thread does cleanup work, and waits for the client's connection or other queries again until the client enters the QUIT command, which is the end of the session. (1.5) Supplement -1:mysql daily 90% of the work as described in the process is running, but ther

)--July Sales Amount Month8 Number (10,2)--August Sales Amount Month9 Number (10,2)--September Sales Amount Month10 Number (10,2)--October Sales Amount Month11 Number (10,2)--November Sales Amount Month12 Number (10,2)--December Sales Amount The SQL statements for structure conversions are: Create or Replace view V_sale (YEAR,MONTH1,MONTH2,MONTH3,MONTH4,MONTH5,MONTH6,MONTH7,MONTH8,MONTH9,MONTH10,MONTH11,MONTH12) As Select SUBSTRB (month,1,4), SUM (Decode (SUBSTRB (month,5,2), ' sell,0 '), SUM (D

　　Various scheme references printed in Rdiframework.net━web-Welcome supplement　　Web development of the comrades should have a deep understanding, in the Web program printing is no longer as easy to control in the application, Web programs inherent in some of the characteristics of this disadvantage, such as: The printer is local, and the file may be on the server, how the format control and customization, and so on, has brought a lot of problems in ou

this section(i) CSS Supplement(b) JS (i) CSS Supplement1.positionA. fiexd ==> fixed to a location on the page"en">"UTF-8"> "gotop ();"style="width:50px; height:50px;background-color:black;color:white;position:fixed; bottom:20px; right:20px; "> Back to top "Height:5000px;background-color: #dddddd"> View Code"en">"UTF-8"> class="Pg-header"> Head class="Pg-body"> Content keep the menu pinned foreverEffect:B.absolute + Relative"en">"UTF-8"> "posit

Some Supplement and description of component development technology under XPCOM--LINUXOriginal article from: World Business comments icxo. com (date)--------------------------------------------------------------------------------Boise bjgxjob@163.com--------------------------------------------------------------------------------As a component technology implemented by Microsoft, COM technology plays an important role in the Windows platform station an

I have written an article about using the JqueryAjax method to pass values to actions. This article is a supplement to this article. I have written an article about using the Jquery Ajax method to pass values to actions, this article is a supplement to this article Assume that the method in controller is as follows: The Code is as follows: Public ActionResult ReadPerson (PersonModel model){String s = mod

CentOS-based Mysql learning Supplement 2-using Shell to create a database, centosmysql Article Source: CentOS-based Mysql learning Supplement 2-using Shell to create a database For how to use the mysql database based on commands, see the "Instructions for using CentOS-based Mysql". This article only describes how to use the Shell script to create the database we want, the following is a Shell script for c