Database Administrator

I have never carefully understood the UPDATE lock. I recently saw a problem on the MSDN forum asking about the deadlock issue of heap table UPDATE. The problem is very simple. There are tables and data like this: Create table dbo. tb ( C1 int, C2

When using HibernateDaoSupport in spring-framework-3.2.4 and hibernate-release-4.3.5, an exception occurs in java. lang. classCastException: org. springframework. orm. hibernate4.SessionHolder cannot be cast to org. springframework. orm.

For example, there are two phases in table 1 and table 2, and you want to use like for join queries // use concat to connect the string select t1.id, t1.title, t2.keyword from t1 inner join t2 on t1.title like concat ('%', t2.keyword, '% ');//

Database linke is the object that establishes the path from one database to another. database link allows you to query remote tables. In my understanding, it can be regarded as a distributed database usage. Database link is a one-way connection.

1. Composite data type-record type Ø syntax format Type name is record ( Field 1 Field 1 type [not null]: = expression 1; Field 2 Field 2 type [not null]: = expression 2; ... ) Description: records must be of the same type when values are assigned

Another brother asked for help today. A table in the database has the following data:No name12 B3 c4 dUse an SQL statement to display the following results:ABAcAdBcBd Cd This kind of constructed data is the strength of the analysis function. Let's

Database Version: SQL> select * from v $ version; BANNER----------------------------------------------------------------Oracle Database 10g Enterprise Edition Release 10.2.0.5.0-64biPL/SQL Release 10.2.0.5.0-ProductionCORE 10.2.0.5.0 ProductionTNS

The company has launched a new service to the data center. The hardware is IBM X3850 X5. The hardware configuration is good, and the memory is 128 GB. SA has installed the system (sule 32bit) and notifies me to install the database. Busy for half a

Union: Perform Union operations on two result sets, excluding duplicate rows, and sort the default rules at the same time; Union All: Perform Union operations on the two result sets, including duplicate rows without sorting; Intersect: intersection

The file is as follows. Modify the file as needed: #/Usr/share/mysql/my-huge.cnf# MariaDB configuration file sample template (huge, giant ).## This file applies to dedicated database servers with a memory of 1 GB to 2 GB.# Only large MariaDB systems

The daily DBA's job is to get the SP code for analysis or transplantation to other environments. How to quickly obtain the sp ddl, DB2 provides many methods to obtain the sp ddl language for reference: 1 select routinename, text from sysibm.

DB2 10 introduces a more management method for tablespaces that manage data storage based on temperature, but requires the database to enable automatic storage management. The specific storage path is in a directory, it takes two steps to convert a

1. the Oracle 10g Stream table-level replication configuration () was previously implemented. If a replication environment already exists, you need to clear the existing replication environment before configuring other types of replication,

Preface In addition to installing the Oracle database software, we often need to install the Oracle client on a host without an Oracle database environment to access the Oracle server over the network. The steps for installing the Oracle Instant

Delete the database that has been created in the Oracle database and reinstall the new database according to the backup oracle path. The path and database SMID must be exactly the same as the original one. Stop all Oracle services, go to the oracle

The customer requested that hive be used to implement the decode function similar to orale. Okay, start work. Oracle decode function Syntax: DECODE (value, if1, then1, if2, thne2, if3, then3,... else ). The first problem involved is the dynamic

Oracle Net is an indispensable component in the process of using Oracle. For beginners, the three configuration files tnsname. ora, listener. ora, and sqlnet. ora are the most confusing parts. Besides, configuration errors are easily caused by the

1. Data File byte sortingThe Oracle platform generally uses two different byte sorting schemes (the ending number format ).If multiple platforms use different byte sorting schemes, you need to use the convert command in RMAN to convert the

Cursor sharing Cursor is a key and difficulty in Oracle learning. Oracle's Cursor is based on the optimization of SQL parsing Parse consumption. Based on different memory cache structures, we often hear terms such as Hard parsing Hard Parse, Soft

If you want to prohibit an IP address from accessing the Oracle database, you can use the Valid Node Verification function. 1. Set in $ ORACLE_HOME/network/admin/sqlnet. ora: TCP. VALIDNODE_CHECKING = yes TCP. EXCLUDED_NODES = NODES = (finance.us.