oracle11gr2

问题 This question already has answers here : SQL Query to concatenate column values from multiple rows in Oracle (11 answers) Closed 2 years ago . I have a Oracle 11g XE database and I have a query the result set: ID Category 1 Cat1 1 Cat2 2 Cat3 2 Cat4 I want to get distinct id's with all related categories in same row as comma separated like this ID Categories 1 Cat1,Cat2 2 Cat3,Cat4 I was using Postgres before and array_agg helped me there. How can I get same result in Oracle 11g XE? 回答1:

问题 Oracle JDBC supports two distinct models for update batching: Standard Batching and Oracle Specific Batching. According to oracle 11g JDBC Developer Guide, in any single application, you can use one model or the other, but not both. Oracle JDBC driver will throw exceptions when you mix these . In my standalone application, the above statement does not hold true. I want to know if I am missing something. In my application I create a OracleDataSource and do the following connection = datasource

问题 I have a requirement to use the built in REPLACE function on a CLOB variable as part of a larger PL/SQL process. I'm using Oracle 11g R2 and the function works OK, in that it does the replace as required, but as the procedure runs (there are around 2.5 millions records to process), it slows down badly - as in: first 20,000 records: ~12 minutes second 20,000 records: ~24 minutes third 20,000 records: ~37 minutes fourth 20,000 records: ~52 minutes etc... Checking V$TEMPORARY_LOBS during

问题 I suddenly noticed that Oracle JDBC driver that I was using With Oracle 11g R2 was thinking that daylight savings time in US started after 2:59:59 am on March 13th this year. Actually, it started after 1:59:59 am. I did some additional testing and noticed that the buggy behavior of that driver did not depend on whether it talks to Oracle 11g R2 or Oracle 10g. Also, all available previous versions of that driver handle daylight savings time change correctly. Is this a known bug? Is there a fix

问题 I have a table MYTABLE with a date column SDATE which is the primary key of the table and has a unique index on it. When I run this query: SELECT MIN(SDATE) FROM MYTABLE it gives answer instantly. The same happens for: SELECT MAX(SDATE) FROM MYTABLE But, if I query both together: SELECT MIN(SDATE), MAX(SDATE) FROM MYTABLE it takes much more time to execute. I analyzed the plans and found when one of min or max is queried, it uses INDEX FULL SCAN(MIN/MAX) but when both are queried at the same

问题 I have a table MYTABLE with a date column SDATE which is the primary key of the table and has a unique index on it. When I run this query: SELECT MIN(SDATE) FROM MYTABLE it gives answer instantly. The same happens for: SELECT MAX(SDATE) FROM MYTABLE But, if I query both together: SELECT MIN(SDATE), MAX(SDATE) FROM MYTABLE it takes much more time to execute. I analyzed the plans and found when one of min or max is queried, it uses INDEX FULL SCAN(MIN/MAX) but when both are queried at the same

问题 I have a table MYTABLE with a date column SDATE which is the primary key of the table and has a unique index on it. When I run this query: SELECT MIN(SDATE) FROM MYTABLE it gives answer instantly. The same happens for: SELECT MAX(SDATE) FROM MYTABLE But, if I query both together: SELECT MIN(SDATE), MAX(SDATE) FROM MYTABLE it takes much more time to execute. I analyzed the plans and found when one of min or max is queried, it uses INDEX FULL SCAN(MIN/MAX) but when both are queried at the same

问题 This question is related to my original issue How to return an array from Java to PL/SQL ?, but is a more specific. I have been reading Oracle Database JDBC Developer's Guide and Creating ARRAY objects Server-Side Internal Driver oracle.jdbc.OracleConnection oracle.jdbc.OracleDriver but I still fail to write a minimum code where I can create ARRAY using ARRAY array = oracle.jdbc.OracleConnection.createARRAY(sql_type_name, elements); as instructed in Creating ARRAY objects. I'm using Oracle

问题 I need to open a cursor while table name, columns and where clause are varying. The table name etc will be passed as parameter. For example CURSOR batch_cur IS SELECT a.col_1, b.col_1 FROM table_1 a inner join table_2 b ON a.col_2 = b.col_2 WHERE a.col_3 = 123 Here, projected columns, table names, join criteria and where clause will be passed as parameters. Once opened, i need to loop through and process each fetched record. 回答1: You need to use dynamic SQL something like this: procedure

问题 Is the built in ability of PostgreSQL and Oracle Object-Relational mapping the same as an ORM like Hibernate, SQLAlchemy, or Doctrine? Are these databases queried and used just like objects you'd get back from ORMs? EDIT: Do I misunderstand what an ORDBMS is? Stil learning. http://www.postgresql.org/docs/8.2/static/intro-whatis.html http://docs.oracle.com/cd/E11882_01/appdev.112/e11822/toc.htm EDIT: I found it here also. http://en.wikipedia.org/wiki/Comparison_of_object-relational_database