Oracle

Data Guard provides the following three kinds of protection mode, the following is a detailed analysis of the three protection modes, the need for friends can refer to the next The data guard provides the following three kinds of protection modes:

Oracle has three kinds of table connectivity technologies, namely, nested joins, merge joins, and Hash joins. The following is a detailed analysis of the three kinds of table connection algorithm, the need for friends can refer to the 1. Nested loop

Oracle Error Code Encyclopedia-the latest and most complete Oracle error code is helpful for finding Oracle database errors quickly ORA-00001: Violation of UNIQUE constraint (.) ORA-00017: Request session to set trace event ORA-00018: Maximum

0x01 backgroundOracle is similar to MySQL features, semi-automated fuzz, recording results.0x02 Test Position One: The position between the parameter and the Union1) White space charactersThe white space characters available in Oracle are:%00%09%0a%0

Oracle Advanced Query (instance based on four Scott users table)Group queriesMulti-Table QuerySub-queryComprehensive examples=======================================================================Four tables for Scott users

--Query for the slowest SQLSELECT * FROM (Select Parsing_user_id,executions,sortsCommand_type,disk_reads,sql_text from V$sqlarea ORDER BY disk_reads Desc) Where rownum--Query corresponding sessionSelect SE. Sid,se. Serial#,pr. SPID,SE. Username,se.

1. Create ODBC2. Copy the INITDG4ODBC under product\11.2.0\dbhome_1\hs\admin\ and change the name to Initcrmsql (the name of the ODBC created by init+)Hs_fds_connect_info =crmsql #odbc名称HS_FDS_TRACE_LEVEL = 0hs_fds_recovery_account=sa

I built the Oracle database in the debugging of their own stored procedures to write the prompt for the lack of debug Connect session permissions, under the general circumstances under this prompt directly with the Administrator account log in,

　　Due to a careless operation, there was no success in switching table space, but because the undo_management value of parameter undo was changed to Manual, no error was reported when starting the database, but inserting the data times to the table

Oracle Basic data types (also called built-in data types built-in datatypes) can be categorized by type: String type, Number type, date type, LOB type, LONG raw& RAW type, ROWID & urowid type.Before Apple told the string type, let's talk about

1. What is a transactionIn a database, a transaction is a logical unit of work, a transaction consists of one or more SQL statements that complete a set of related behaviors, ensuring that the operations of this set of SQL statements are executed

Recent database experiments with VMware virtual machines for Oracle. As we all know on Windows, I was able to go to the delete program to take the initiative to delete all of the installed applications. However, there is no such service on Linux

The "preface" is explained in the blog post:This article will introduce a personal tone about the Oracle database import and export knowledge, at the current point in time "May 16, 2017 " under the mastery of limited technology, there may be a lot

The Oracle database is one of the most applied databases. General Project Application. Deploying Oracle in the Intranet, intranet calls, and operations can only be done on the intranet.Suppose the Oracle host or local area network does not have a

DB file Sequential read:Website Explanation:This event signifies, the user process is reading a buffer to the SGA buffer cache and is waiting for a physical I/Ocall to return. A sequential read is a single-block read.The single block I/Os is usually

JDBC reads the Oracle long RAW field with text in itReference:http://singlewolf.iteye.com/blog/278769http://blog.csdn.net/restraint/article/details/7190265http://blog.csdn.net/bq1073100909/article/details/49335491String sql = "Select condition from

Talk about the system permissions of Oracle database unlimited tablespaceAuthor: Zhao Full text network name: GuestThe morning before yesterday, the development of student feedback, the application is connected to a set of Oracle 11.2.0.4.0 database

The first step: Download the instant client package on the ORALCE official website to load the Oracle instantclient Basic packages. The address is as follows:

The fact that TNS cannot be resolved is a common problem in Oracle operations for two reasons:(1) Oracle server is not installed (generally not recommended for reloading, because Oracle offload is not completely impossible to reinstall)(2) TNS is

1. Oracle Data typeOracle's data types are as followsString type char nchar varchar2 NVARCHAR2numeric type int number integer smallintDay Type Date TimestampCustom type Create typeHere the UDT represents the Oracle custom type, the syntax is as