![]() ![]() This usually means that a 64 bit number for UID or a uuid field for EPC should be enough. In most applications you will just receive the UID or EPC of the tag, and you will need to store only that. ![]() Some models do have it, but it is usually very limited (128 or 256 bits). UHF tags are mostly used for logistics and tracking and many tags do not have user memory. ![]() Each application / system integrator usually programs the EPC according to the needs of the application UHF tags, on the other hand, usually have a 96 or 128 bit EPC (256 bit EPC models are emerging), that is not generally unique and it is reprogrammable. It is not common to have to store the contents of this data in an external database, but if you do, you need to know the model of the IC. There are 3 types of PL / SQL collection structures. The difference of the collections from the arrays is that their dimensions can be changed when new elements are added or requested. HF tags usually have some user memory too, that can vary from a few bits to usually a maximum of 4Kbits, but special application ICs exist with memory up to 80-90Kbit (i.e. Collections are used to store data of the same data type in a variable, such as arrays contained in PL / SQL. HF tags are usually used for ticketing, anti counterfeiting, brand protection applications. The UID is usually guaranteed to be unique by the producer of the IC and is read only. HF tags usually have one Unique Identifier, called UID, that is 64 bits in size. Now the people_tab table is in the system tablespace and the nested table storage is stored in the example tablespace.RFID today is made basically of two standards, being HF (13.56MHz) and UHF (800-900MHz depending if Europe/US) For example:ĪLTER TABLE people_tab MOVE TABLESPACE system - moving tableĪLTER TABLE people_column_nt MOVE TABLESPACE example - moving storage table create a collection type CREATE TYPE myobjtab AS TABLE OF myobj - have the function return a collection type CREATE OR REPLACE function f return myobjtab IS objtab myobjtab begin objtab : myobjtab(myobj(1,'test')) return objtab end f - CAST it as a table and straight up. To move a storage table for a nested table to a different tablespace, issue ALTER TABLE. You can create a collection and cast it in the SQL. If you do this on a table with nested table columns, only the parent table moves no action is taken on the storage tables of the nested table. MOVE statement to move a table to a different tablespace. For multilevel nested tables, Oracle creates the child table in the same tablespace as its immediately preceding parent table. The following example implements the ICollection interface to create a collection of custom Box objects named BoxCollection.If the TABLESPACE clause is not specified, then the storage table of the nested table is created in the tablespace where the parent table is created. NESTED TABLE people_column STORE AS people_column_nt ( TABLESPACE system) See " Collection Querying".Įxample 5-6 Specifying a Different Tablespace for Storing a Nested Table - Requires Ex. TABLE(s.math_majors) m, TABLE(s.chem_majors) c, TABLE(s.physics_majors) p Ī convenient way to access the elements of a nested table individually is to use a nested cursor or the TABLE function. SELECT m.idno math_id, c.idno chem_id, p.idno physics_id FROM students s, The Oracle SQLJ implementation supports either strongly typed. The LIST object must have a first element, which can be followed by a second element. The elements of a LIST data type have ordinal positions. The LIST data type supports, but does not require, duplicate element values. Oracle objects and collections are composite data structures consisting of individual data elements. The LIST data type is a collection type that can store ordered non-NULL elements of the same SQL data type. INSERT INTO students (graduation) VALUES ('01-JUN-03') The Oracle SQLJ implementation supports user-defined SQL object types, which are composite data structures, related SQL object reference types, and user-defined SQL collection types. My problem is some columns have different datatype. I am trying to get a datatype using pyspark. Collection column has two different values (e.g.: (bson.Int64,int) (int,float)). NESTED TABLE physics_majors STORE AS physics_majors_nt ĬREATE INDEX math_idno_idx ON math_majors_nt(idno) ĬREATE INDEX chem_idno_idx ON chem_majors_nt(idno) ĬREATE INDEX physics_idno_idx ON physics_majors_nt(idno) We are reading data from MongoDB Collection. NESTED TABLE chem_majors STORE AS chem_majors_nt NESTED TABLE math_majors STORE AS math_majors_nt - storage tables Math_majors people_typ, - nested tables (empty) Example 5-5 Creating and Populating Simple Nested Tables - Requires 5-1 ![]()
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