rowid

问题 What is the data type of ROWID in Oracle/SQL? How is this value stored? 回答1: The following link explains what the data type for ROWID is - ROWID data type ROWID is stored as a psuedocolumn. 回答2: The ROWID (since Oracle8 called extended ROWID, till Oracle7 now called restricted ROWID) stores/encodes the physical location of a row. The (extended) ROWID encodes (in hexadecimal format) the following fields: OBJID (unique id of the object the row belongs to), the FILENO (relative file number

问题 What's the equivalent of Oracle's RowID in SQL Server? 回答1: From the Oracle docs ROWID Pseudocolumn For each row in the database, the ROWID pseudocolumn returns the address of the row. Oracle Database rowid values contain information necessary to locate a row: The data object number of the object The data block in the datafile in which the row resides The position of the row in the data block (first row is 0) The datafile in which the row resides (first file is 1). The file number is relative

问题 What's the equivalent of Oracle's RowID in SQL Server? 回答1: From the Oracle docs ROWID Pseudocolumn For each row in the database, the ROWID pseudocolumn returns the address of the row. Oracle Database rowid values contain information necessary to locate a row: The data object number of the object The data block in the datafile in which the row resides The position of the row in the data block (first row is 0) The datafile in which the row resides (first file is 1). The file number is relative

问题 I have the below sample table: create table data_test ( data_id number, data_value varchar2(100) ); I want to use this as a nested table parameter in the below sample Stored Procedure by doing the below declaration: create or replace package dat_pkg is type typ_dat_tst is table of data_test%rowtype index by pls_integer; procedure proc_test (p_dat typ_dat_tst); end dat_pkg; / I want proc_test to update the rows of data_test based on the rowid of the nested table: create or replace package body

问题 I have a table that has a lot of duplicated rows and no primary key. I want to remove just the duplicated records, but when I try to do this it would remove all peers. How can I find the ROWID from a table in Postgres? 回答1: Simplify this by one query level: DELETE FROM table_name WHERE ctid NOT IN ( SELECT min(ctid) FROM table_name GROUP BY $other_columns); .. where duplicates are defined by equality in $other_columns . There is no need to include columns from the GROUP BY clause in the

问题 AFAIK ROWID in Oracle represents physical location of a record in appropriate datafile. In which cases ROWID of a record may change ? The one known to me is UPDATE on partitioned table that "moves" the record to another partition. Are there another cases ? Most of our DBs are Oracle 10. 回答1: As you have said, it occurs anytime the row is physically moved on disk, such as: Export/import of the table ALTER TABLE XXXX MOVE ALTER TABLE XXXX SHRINK SPACE FLASHBACK TABLE XXXX Splitting a partition

问题 My understanding is that the ROWID is a unique value for each row in the result returned by a query. Why do we need this ROWID? There is already the ROWNUM in ORACLE. Have any one used ROWID in a SQL query? 回答1: ROWID is the physical location of a row. Consequently it is the fastest way of locating a row, faster even than a primary key lookup. So it can be useful in certain types of transaction where we select some rows, store their ROWIDs and then later on use the ROWIDs in where clauses for

问题 I've created an external SQLite database that looks something like this: What I want to do in my Android application is to load all the values from one row using ROWID and put them into array. For example: Cursor cursor = db.rawQuery("SELECT * FROM Dairy WHERE ROWID = 1", null); This would return all the values from row 1: 51, 35, 63. However, this always returns just first value, in this case 51. Also, the cursor.getCount() always returns 1. Here's my complete code: db = getReadableDatabase(

问题 I just would like to hear different opinions about ROWID type usage as input parameter of any function or procedure. I have normally used and seen primary keys used as input parameters but is there some kind of disadvantages to use ROWID as input parameter? I think it's kind a simple and selects are pretty quick if used in WHERE clause. For example: FUNCTION get_row(p_rowid IN ROWID) RETURN TABLE%ROWTYPE IS... 回答1: From the concept guide: Physical rowids provide the fastest possible access to

问题 I perform an insert on a database and I want to know what the rowid is for that insert. Does this accomplish the task: Uri uri = ContentResolver.insert(url,values); //Make insert int rowid= Integer.parseInt(uri.getFragment()); //Get rowid The Android documentation states that the insert returns "the URL of the newly created row." And the Uri method getFragment() is supposed to return everything after the /#. So, is my understanding correct that getFragment() would thus return to me the rowid?