[Lone solitary Nine swords] Oracle Knowledge Point Grooming (10)%type and%rowtype and common functions

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[Lone solitary Nine swords] Oracle Knowledge Point Grooming (a) table space, user

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (ii) connection of databases

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (iii) Import, export

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (iv) DML and DDL for SQL statements

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (v) table, View of common objects in database

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (vi) procedure, function and Sequence of common objects in database

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (vii) Cursor of common objects in database

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (eight) common exception

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (ix) database common objects of the package

[Lone solitary Nine swords] Oracle Knowledge Point Grooming (10)%type and%rowtype and common functions

5.8. The concept of%type and%rowtype

When defining a variable, use Person.name%type to set the variable type to the same type as the name field of the person table
Using V_roomrecord Rooms%rowtype is to align the structure of the V_roomrecord with the table structure of the table rooms

5.9, about the record, varray, table of the use of detailed

http://blog.csdn.net/liangweiwei130/article/details/38223319

5.10. Common functions in Oracle 5.10.1 Merge all fields of a column in a query result

Select  from where -- concatenate the Name field with commas

5.10.2 trunc Processing Date fields

Date format result can be obtained.

1 Select  from person;    -- get the date of birth of the person 2 Select  from where between trunc (sysdate-1and-- to find out who was born yesterday and today

5.10.3 concat merging two parameters

1 Select concat (' Harry ',' potter ' from-- get Harry Potter 2 Select  from -- get the name and age of the merged column

5.10.4 Type Conversions

1To_char (123)--> ' 123 '2To_number ('123')--> 1233To_date ('2015-03-15','YYYY-MM-DD')--March 15, 2015 of the > Time type4To_date ('2015-03-15 20:10:10','YYYY-MM-DD Hh24:mi:ss')--March 15, 2015 20:10:10 of the > Time type

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[Lone solitary Nine swords] Oracle Knowledge Point Grooming (10)%type and%rowtype and common functions