oracle10g

问题 I have a question in mind about the insert mechanism in different databases. Supposing a table with a single column primary key that is automatically generated (like identity columns), will the entire table become locked when inserting a new record? and if the insert takes too much time, will the other transactions have to wait more? 回答1: By default Oracle uses row level locks. These locks are blocking only for writers(update, delete, insert etc). That means select will works all the time

问题 How can I read blob data in Oracle SQL Developer. It is stored in byte[] format. Is there any possibility to read in string format. 回答1: Follow these steps in Oracle SQL Developer - Open data window of your table. The BLOB cell will be named as (BLOB) . Right click the cell. You will see a pencil icon. Click on it. It will open a blob editor window. You would find two check boxes against the option View as : Image or Text . Select the appropriate check box. If above step is still convincing,

问题 Name Null Type ------------------ -------- -------------- RESOURCE_ID NOT NULL NUMBER(38) RESOURCE_FIRST_NM NOT NULL VARCHAR2(30) RESOURCE_MIDDLE_NM VARCHAR2(30) RESOURCE_LAST_NM NOT NULL VARCHAR2(30) RESOURCE_TYPE_CD NOT NULL VARCHAR2(10) EMPLOYEE_ID VARCHAR2(20) EMPLOYEE_TYPE_CD VARCHAR2(10) FUNCTIONAL_LEAD_CD VARCHAR2(10) PHONE_1 VARCHAR2(15) PHONE_2 VARCHAR2(15) FAX_NR VARCHAR2(15) EMAIL_DE VARCHAR2(50) RESOURCE_STATUS_CD NOT NULL VARCHAR2(10) HIRING_DT NOT NULL DATE LEAVE_START_DT DATE

问题 i have table that has millions of rows that i need to join to do selects. the response time is not so good, how can i improve its response? i have tried adding index to the columns i do select by, is there a tool i can use to optimize the sql or how can i diagnose on the bottlenecks of the sql and improve it? any suggestion would be very appreciated. i am using oracle server 10g and using asp.net as my client. is there any other kind of indexing helpful on tables with millions of rows? 回答1:

问题 I'm trying to run multiple ddl statements within one Execute Immediate statement. i thought this would be pretty straight forward but it seems i'm mistaken. The idea is this: declare v_cnt number; begin select count(*) into v_cnt from all_tables where table_name='TABLE1' and owner = 'AMS'; if v_cnt = 0 then execute immediate 'CREATE TABLE TABLE1(VALUE VARCHAR2(50) NOT NULL) ALTER TABLE TABLE1 ADD (MYVAL2 NVARCHAR2(10))'; end if; end; however this results in an error ORA-00911: invalid

问题 I'm working with an Oracle 10g database, and I want to extract a group of records from one table, and then use that for pulling records out of a bunch of related tables. If this were T-SQL, I'd do it something like this: CREATE TABLE #PatientIDs ( pId int ) INSERT INTO #PatientIDs select distinct pId from appointments SELECT * from Person WHERE Person.pId IN (select pId from #PatientIDs) SELECT * from Allergies WHERE Allergies.pId IN (select pId from #PatientIDs) DROP TABLE #PatientIDs

问题 Oracle Details:- Oracle 10g Enterprise Edition Host running XP x32 I use scott tiger for logging with SQL* Plus . I dont provide any HOST STRING . How can i setup Oracle to accept Host String ? i am asking this because i guess the problem is related to this IP : 192.168.17.132 , Hostname : vmxp1 tnsnames.ora file:- GLOBALDB = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = vmxp1)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = globaldb) ) ) EXTPROC_CONNECTION_DATA =

问题 I have some code: @Id @SequenceGenerator(name = "SOMETHING_SEQ") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SOMETHING_SEQ") @Column(name = "SOMETHING", nullable = false) private Long id; How is hibernate providing my id? I see in my database there a single sequence named 'hibernate_sequence' and no other hibernate 'special tables'. 回答1: Actually, here your SOMETHING_SEQ is the name of sequence you configured somewhere in your hibernate config. And hibernate_sequence is

问题 SELECT col1 'COLUMN 1' FROM TABLENAME I am getting an error 'from keyword not found where expected' How can you give column alias in Oracle 10g some examples are appreciated 回答1: Use double quotes: SELECT col1 "COLUMN 1" FROM TABLENAME 回答2: Shepherdess is correct - you can't use single quotes here. If the alias doesn't have spaces, you could just type the name without any quotes: SELECT col1 column1 FROM TABLENAME 回答3: Single quotes is not allowed here .Either you have to use double quotes or

问题 Scenario : We have an application that is using Oracle 10g and the latest version of ODP.net within an ASP.net application. We are utilizing the .ClientID WriteOnly property on the OracleConnection object to pass in a specific UserID to the database for auditing purposes. When Connection Pooling is disabled, this works perfectly. When it is enabled, the first person who logs in (ex: USER1) updates a record and the MODIFIED_BY is USER1, but when a different user heads into the website after,