database-partitioning

问题 Is it possible to partition based on char column? After reviewing the MySQL 5.1 documentation it appears that only integer types can be used. Is this correct? Or can I use some function to convert the char into an integer? The char field in question contains a unique identifier. 回答1: Partitioning in MySQL 5.1 can only deal with integer columns (Source). You can only use a few partitioning functions on non-integer columns. For example: CREATE TABLE ti (id INT, amount DECIMAL(7,2), tr_date DATE

问题 Thanks in advance for any help with this, it is highly appreciated. So, basically, I have a Greenplum database and I am wanting to select the table size for the top 10 largest tables. This isn't a problem using the below: select sotaidschemaname schema_name ,sotaidtablename table_name ,pg_size_pretty(sotaidtablesize) table_size from gp_toolkit.gp_size_of_table_and_indexes_disk order by 3 desc limit 10 ; However I have several partitioned tables in my database and these show up with the above

问题 I want to use a Composite Range-List Partitioning in oracle. Using a range is pretty clear to me. The tricky part is on the list partition and this is where i have the question. Let's assume we have a column with continents. I want the list partition that to include all the continents that are NOT Europe. The problem here is that i cannot create a list partition including all other continents except of Europe, as at some point i might add new continents. Is something like this possible? 回答1:

问题 I have Oracle version 12.2.0.1.0 We have generic script which create sequence that need to be reuse for different objects (by renaming sequence name): CREATE SEQUENCE NAME_SEQ MINVALUE 1 MAXVALUE 999999999 INCREMENT BY 1 START WITH 100 CACHE 200 NOORDER NOCYCLE NOPARTITION ; This script isn't working with below error until I remove NOPARTITION : ORA-00933: SQL command not properly ended I found in AskTom that the NOPARTITION is not supported in 12.2 there's been various of things in previous

问题 Excuse me for my english. I have 2 tables, both partitioned by date interval, but on different fields. There is a big amount of records in both tables(~100kk in each partition). First table keep it's 3 last(by date) partitions in fast discks tablespace, others partitions is in slow discks tablespace. Also I have some system, which processing data. It execute processes in parallel, each one get data from first table by select statement and put processed data into second table. So I need select

问题 I am writing a data warehouse, using MySQL as the back-end. I need to partition a table based on two integer IDs and a name string. A more concrete example would be to assume that I am storing data about a school. I want to partition the school_data table based on COMPOSITE 'Key' based on the following: school id (integer) course_id (integer) student_surname (string) For the student surname, it is just the first character of the surname that determines which 'partitioned table' the data

问题 I have a huge partitioned table stored at a PostgreSQL table. Each child table has an index and a check constraint on its id, e.g. (irrelevant deatils removed for clarity): Master table: points Column | Type | Modifiers ---------------+-----------------------------+------------------------ id | bigint | creation_time | timestamp without time zone | the_geom | geometry | Sub-table points_01 Column | Type | Modifiers ---------------+-----------------------------+------------------------- id |

问题 High Water Mark (HWM) for a table in an Oracle Database is the line between blocks that have been used and ones that have never been. Truncating a table resets the HWM to zero. Now, if I have a partitioned table, I'd like to know if the following is true: Does each partition maintain its own HWM? If not, does alter table ... drop partition ... affect table's HWM? The idea is I'd like to populate partition's tables with insert /*+ append */ (direct path insert), but it only writes data beyond

问题 High Water Mark (HWM) for a table in an Oracle Database is the line between blocks that have been used and ones that have never been. Truncating a table resets the HWM to zero. Now, if I have a partitioned table, I'd like to know if the following is true: Does each partition maintain its own HWM? If not, does alter table ... drop partition ... affect table's HWM? The idea is I'd like to populate partition's tables with insert /*+ append */ (direct path insert), but it only writes data beyond

问题 I have an existing table in a postgres-DB. For the sake of demonstration, this is how it looks like: create table myTable( forDate date not null, key2 int not null, value int not null, primary key (forDate, key2) ); insert into myTable (forDate, key2, value) values ('2000-01-01', 1, 1), ('2000-01-01', 2, 1), ('2000-01-15', 1, 3), ('2000-03-02', 1, 19), ('2000-03-30', 15, 8), ('2011-12-15', 1, 11); However in contrast to these few values, myTable is actually HUGE and it is growing continuously