Oracle

I wanted to download JDK through the following command on Linux. Wget Https://edelivery.oracle.com/otn-pub/java/jdk/7u5-b06/jdk-7u5-linux-x64.rpm Only download the HTML file download-fail-1505220.html. This is because Oracle requires OTN before

Cast converts the Data Types of Oracle databases and modifies the data types of users. Round only modifies the data display format. Round the data. Similar functions include Ceil (the smallest integer of the data). trunc (the entire function .)

Unfortunately, someone accidentally deleted the created table ,,, Fortunately, you can recover it in this way.   Select * From user_recyclebin where original_name like 'finance _ % 'order by droptime DESC; Flashback table finance_case_fee_item

Oracle driver = "oracle. JDBC. driver. oracledriver "url =" JDBC: oracle: thin :@ localhost: 1521: Database Name "sqlserver driver =" com. microsoft. JDBC. sqlserver. sqlserverdriver "url =" JDBC: Microsoft: sqlserver: // localhost: 1433;

First, add the JDBC and JAR file class12.jar of Oracle. Import java. SQL. connection; Import java. SQL. drivermanager; Import java. SQL. resultset; Import java. SQL. Statement; public class myconnect { Public static void main (string ARGs []) throws

Select T .*From tablekind tWhere (T. column1, T. column2) in('123', '123'), ('123', '123'), ('123', '123 '),('123', '123'), ('123', '123'), ('123', '123 '),('123', '123'), ('123', '123'), ('123', '123 '),('123', '123'), ('123', '123'), ('123', '123 '

Q: How can I maintain excellent performance in Oracle databases? A: You can start from the following aspects: ◆ Partition Based on actual experience, in a large database, the vast majority of database space is occupied by a small number of tables.

133. currval and nextval Create sequence for table Create sequence emsequq ...; Select empseq. currval from dual; Automatically inserted Sequence Value Insert into EMP Values (em1_q. nextval, 'Lewis ', 'cler ', 7902, sysdate, 1200, null, 20 ); 134.

174./* + all_rows */ It indicates that the overhead-based optimization method is selected for the statement block, and the optimal throughput is obtained to minimize the resource consumption. For example: Select/* + all + _ rows */emp_no, emp_nam,

255. chartorowid (char) Convert the char or varchar2 values that contain the rowid of the external signature method to the binary notation of the internal part, char must be an 18-character string containing the rowid of the external signature

V$ view managed by 9i. 401. V $ pq_tqstat Contains statistics on parallel execution operations to help determine imbalance in a query. 402. V $ Process Contains information about the active process. 403. V $ proxy_archivedlog Contains the

1. What is the initial password after Oracle Security is complete? Internal/Oracle Sys/change_on_install System/Manager Scott/Tiger Sysman/oem_temp 2. What is the initial Default User and password of Oracle9iAS Web

9i data dictionary DBA view. 485. dba_2pc_neighbors Contains the inbound or outbound connection information for pending transactions. 486. dba_all_tables Displays the description of all tables in the database. 487. dba_application_roles All roles

There is a table Node ID No. Parent_id Parent node Name Name Self-join. If no parent node exists, the value of parent_id is null, instead of 0, because no node numbered 0 exists. Select * from

Query all nodes and indent them by node.Select * from organ connect by parent_id = prior ID start with parent_id is null; The working method is to first find the record whose parent_id is null, and then expand it layer by layer according to the

I have been involved in the "digital bus" project for more than a month, and I have basically completed and passed the test, This project is based on the Oracle C/S structure and involves many database operations. Some experience is not used in the

Declare sqlstring varchar2 (100); emprow emp_bak % rowtype; myno emp_bak.empno % type; begin -- sqlstring: = 'create table emp_bak as select * From emp'; sqlstring: = 'select * From emp_bak where empno =: myno and Sal>: mysal '; myno: =' &

62. Min (distinct | all)Minimum value. "All" indicates minimum value for all values, and "distinct" indicates minimum value for different values. The same value is used only once.SQL> select Min (all Sal) from Gao. table3; Min (allsal)-----------1111

Usually used to MS-SQL2000, Meng a use of Oracle is really a little uncomfortable. Today, I wrote a query statement. After writing it, I found it was too long. In terms of performance and convenience, it is decided to pass it to the stored procedure

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