oracle10g

问题 I am trying to create a user without any password by using queries- create user abc; create user 'abc'@'localhost'; but neither of them works. It is given on oracle docs that it is valid to create user with no password by including no IDENTIFIED BY clause. Please help me with this query. 回答1: Either use: Oracle wallet. User is identified via password, but the password is not prompted manually. External authentication. CREATE USER XY IDENTIFIED EXTERNALLY; The user XY must then have OS account

问题 Is there a way to exclusively lock a table for reading in Oracle (10g) ? I am not very familiar with Oracle, so I asked the DBA and he said it's impossible to lock a table for reading in Oracle? I am actually looking for something like the SQL Server (TABLOCKX HOLDLOCK) hints. EDIT : In response to some of the answers: the reason I need to lock a table for reading is to implement a queue that can be read by multiple clients, but it should be impossible for 2 clients to read the same record.

问题 I have a LONG column named FileSize in a table called Files. To achieve the objective, I did the following : I wrote this PL/SQL script to find the size declare long_var LONG:=0; begin dbms_output.put_line(length(long_var)); execute immediate 'SELECT FILESIZE INTO long_var FROM FILES'; dbms_output.put_line(length(long_var)); end; But it throws an error : ORA-00905: missing keyword ORA-06512: at line 5 I was doing the following as I saw thw following on the link given below: http://www

问题 I am not able to find any information on if an Oracle 12c client is going to be able to connect to a Oracle 10.1.0.5 server installation (on a diffrent machine). Both in a Windows enviroment. Does anyone have information on this? 回答1: As mentioned in the documentation, note 207303.1 on the Oracle Support site has an interoperability matrix between client and server versions. That says that the 12c client is not supported with a 10.1 server, and indeed that connections will error. (You'll need

问题 I have a table with a CLOB column. I'd like to convert the existing data to a BLOB datatype. That fails with ORA-252858 invalid alteration of datatype . I though about creating a new BLOB column, copying the existing data to it, and then deleting the existing CLOB column. How can I copy from a CLOB column to a BLOB column? 回答1: create table temp(col_clob clob,col_blob blob); insert into temp (col_clob) values('hi i am gaurav soni'); insert into temp (col_clob) values('hi i am gaurav soni');

问题 I am trying to allow users to choose a file from local hard disk and to insert it with java in a Oracle Data base as BLOB value. The setBinaryStream did not allow big files. with the setBlob I have no way to convert the file to a blob. Is the import of a blob file from the DB then overwrite it the unique solution?. Regards, Haythem 回答1: This is a suggestion that I've used before In essence a file is an array of bytes, what you can do is to read the file data and use PreparedStatement.setBytes

问题 I cant understand why I can't find such tool (oracle Forms or Reports decompiler) It's very valuable because many enterprises use oracle based systems. Does anyone know what's special in the .FMX or .REP format files structure that prevents building a decompiler for them ? 回答1: Given the $1.3bn award they just got against SAP for intellectual property infringement, Oracle are probably not the best people to pick on. Either a company has its own in-house developed systems, including source

问题 Friends, In testing our Oracle Forms application on Vista I have found a interesting "challenge". The application can invoke the Microsoft Word spell checker to perform a spell check on a field. When invoked, the user is shown the standard Microsoft Word spell checker dialog window. Word itself is invisble to the user. The Spell Checker is invoked from Forms using Automation and the method used is based on the metalink note: 295449.1 How To Integrate The MS Word Spell Checker With Forms Using

问题 Need help with SQL - I want to generate and update a column in every row with a different random number. Database # Oracle 10g. Example - When I do something like this it updates all the rows with the same number update mytable r set r.generated_num = (select floor(dbms_random.value(100,9999999)) from dual). Any advice? 回答1: Looks like sub-query is the problem. This seems to be working- update mytable r set r.generated_num = TRUNC(dbms_random.value(1,9999999)) 回答2: If you really need a

问题 I'm trying to establish a connection to an Oracle database using BasicDataSource using DBCP. I downloaded commons-dbcp-1.4-bin.zip from here. There are three jar files on the classpath. commons-dbcp-1.4 commons-dbcp-1.4-sources commons-dbcp-1.4-javadoc I'm using the following code for the connection to be established. import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.apache.commons.dbcp.BasicDataSource; public