Table Partitioning Schemes-Partitioning

There are currently nine methods by which you can partition tables in Oracle: •\ Range partitioning: You may specify ranges of data that should be stored together. For example, everything that has a timestamp within the month of Jan-2014 will be stored in partition 1, everything with a timestamp within Feb-2014 in partition 2, and
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Enhanced Statement Performance-Partitioning

The third general (potential) benefit of partitioning is in the area of enhanced statement (SELECT, INSERT, UPDATE, DELETE, MERGE) performance. We’ll take a look at two classes of statements—those that modify information and those that just read information—and discuss what benefits we might expect from partitioning in each case. Parallel DML Statements that modify data
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Internal LOBs-Datatypes

Starting with Oracle Database 11g, Oracle introduced a new underlying architecture for LOBs known as SecureFiles. The prior existing LOB architecture is known as BasicFiles. By default in 11g, when you create a LOB, it will be created as a BasicFiles LOB. Starting with Oracle 12c, when creating a LOB column in an ASSM-managed tablespace,
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LOB Tablespace-Datatypes

The CREATE TABLE statement returned from DBMS_METADATA for both the SecureFiles and BasicFiles included the following:LOB (“TXT”) STORE AS … ( TABLESPACE “USERS” … The TABLESPACE specified here is the tablespace where the LOBSEGMENT and LOBINDEX will be stored, and this may be different from the tablespace where the table itself resides. That is, the
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Range Partitioning-Partitioning

The first type we will look at is a range partitioned table. The following CREATE TABLE statement creates a range partitioned table using the column RANGE_KEY_COLUMN. All data with a RANGE_KEY_COLUMN strictly less than 01-JAN-2021 will be placed into the partition PART_1, and all data with a value strictly less than 01-JAN-2022 (and greater than
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TIMESTAMP WITH TIME ZONE Type-Datatypes

The TIMESTAMP WITH TIME ZONE type inherits all of the qualities of the TIMESTAMP type and adds time zone support.The TIMESTAMP WITH TIME ZONE type consumes 13 bytes of storage, with the extra 2 bytes being used to preserve the time zone information. It differs from a TIMESTAMP structurally only by the addition of these
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Creating a BasicFiles LOB-Datatypes

In 12c and above, to create a BasicFiles LOB, you’ll need to use the STORE AS BASICFILE syntax: SQL> create table t( id int primary key,txt clob)segment creation immediatelob(txt) store as basicfile;Table created. Using the DBMS_METADATA package, we can see the details of a BasicFiles LOB:SQL> select dbms_metadata.get_ddl( ‘TABLE’, ‘T’ ) from dual;DBMS_METADATA.GET_DDL(‘TABLE’,’T’) CREATE TABLE
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LOB STORAGE Clause-Datatypes

And lastly, the CREATE TABLE statement returned from DBMS_METADATA previously included the following for SecureFiles:LOB (“TXT”) STORE AS SECUREFILE (…STORAGE(INITIAL 106496 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)) And here is the corresponding output for BasicFiles:LOB (“TXT”) STORE AS BASICFILE ( …STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS
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