Oracle

When configuring the Oracle JDK development environment, many network tutorials recommend /etc/profile adding environment variables. However, Fedora virtual terminal gnome-terminal is not the default login Shell(can be modified in the configuration),

Develop to a SQL to say to a condition times ORA-22922Code snippet:1 SELECTbag number,2 SUM(actual weight) asactual weight,3 SUM(Volume weight) asvolume weight,4 COUNT(waybill number)

Group by Enhancement sql> Select Deptno,job,sum (SAL) from the EMP Group by deptno,jobsql> +sql> Select Deptno,sum (SAL) from EMP GROUP BY deptnosql> +sql> Select sum (sal) from empsql> sql> ===sql> sql> Select Deptno,job,sum (SAL) fro M EMP GROUP

How to read Oracle Execution PlanFirst, what is the implementation planAn explain plan is a representation of the access path, that's taken when a query is executed within Oracle.Second, how to access dataAt the physical level Oracle reads blocks of

Oracle Use steps: I. Oracle installation two files extracted to the same folder, Doc for description/use of document two. Oracle boot: 1. Start Oracle: Start monitoring and Custom library 2. Start Cmd->sqlplus->sys/java Login Three. Oracle operating

Today, I looked at Oracle intersection and the set, and after that I went through the search for data, after testing, organized as follows:1. and setTable 1:INSERT into student1 values (1, ' Student 1 ');INSERT into student1 values (1, ' Student 2 ')

The WHERE keyword in Oracle cannot be used with aggregate functions, having the ability to filter groups of data after grouping.Usage:SELECT column_name, aggregate_function (column_name)From table_nameWHERE column_name operator ValueGROUP by

　　　　1. query field name in database: Select Column_name,data_type, Data_length,data_precision,data_scale fromUser_tab_columns where table_name= ' table name '; * The table name must be uppercase.2. Querying all user information in the database:

/* divided into four steps *//* Step 1th: Create a temporary tablespace */Create temporary tablespace kmyf_tempTempfile' E:\app\pangxy\product\11.2.0\dbhome_1\kmyf_temp.dbf ' size 50m autoextend onNext 50m maxsize 20480m extent management local;/*

[SQL]View PlainCopy  Update (Select Length (t.name), t.* --name,length (name) From G_enterprise_info T where NVL2 (translate (name, ' \1234567890 ', ' \ '), ' is characters ', ' is number ') = ' is number ' and Asciistr (GSZCDJH)

We know that the Oarcle database really holds the data file (data files), the oarcle tablespace (tablespaces) is actually a logical concept, and he does not physically exist, so a set of data files will be a table space to twist together.Table Space

Installing Oracle under 64-bit Win7 and Win8 can be a hassle, and you'll need to download the appropriate Setup files and environment configuration to get things done.The following are the procedures that I installed:Step 1: Download the files you

First, Parallel1. UseForcibly enables parallelism to execute the current SQL. This version can be used after Oracle 9i, and the previous version does not have an environment to test now. That said, with this description, you can forcibly enable the

Oracle recursive queries (single table with multilevel hierarchy)Http://www.cnblogs.com/walk-the-Line/p/4882866.html-- Find all child nodes under all first layers (including) select m.*,level from with='1' by = m.parent;Oracle Connect by usageHttp:

In Oracle, if the listening log files are not truncated (scheduled cleanup), then the listening log files become larger, because some older OS does not support more than 2GB of files, Therefore, when the Listener.log file exceeds 2GB, it will be

Oracle Database StatementsOracle supports five types of integrity constraintsNot NULL (non-NULL)-prevents null values from entering the specified column, defined on a single column basis, and by default, Oracle allows null values in any column.Check

When the. NET background uses EF to connect to Oracle, if you do not explicitly specify the schema, you will get an error (the table is not found), which is examined below:1, tracking Oracle backstage, EF FirstOrDefault, the conversion is ordinary

1. Copy the table structure and its data:CREATE TABLE Table_name_new as SELECT * from Table_name_old2. Copy only the table structure:CREATE TABLE Table_name_new as SELECT * from Table_name_old where 1=2;Or:CREATE TABLE table_name_new like Table_name_

Preface: When using Oracle database, it is found that Oracle does not have an autogrow column to implement the primary key, so this record is learned. (PS: If there are errors or deficiencies in the place also ask for help point out)Second, sequence

Today do bootstrap treeview, require input Node ID ID, parent node ID PID, textBut the SQL aliases executed are all uppercase, so the question of how to find the next ORCL alias is lowercaseThe code is as follows:Select t.fun_id "pid", T1. fun_id id,