Oracle

An error is prompted when you use an SQL statement to insert data into the long field in Oracle: I have such a problem. In the C # component, I use oledbcomment. executenonquery () method executes an SQL statement that updates a long string to a

1. Create a table Create Table Name ( Column name 1 type, Column name 2 type ); 2. Modify class attributes Alter table table name modify (column name type ); 3. Add Columns Alter table table name Add (column name type ); 4. Add primary key

It is also strange to say that there will be so many problems when we get this thing for the first time. After studying Oracle connections for more than a day, there is a query problem. It is also strange to say that the Chinese fuzzy query in the

The table below shows the ADO data type mapping between access, SQL Server, and Oracle: Datatype Enum Value Access Sqlserver Oracle Adbigint 20   Bigint (SQL Server 2000 +)   Adbinary 128  

--------- Mathematical functions 1. Absolute ValueS: Select ABS (-1) ValueO: Select ABS (-1) value from dual 2. INTEGER (large)S: Select ceiling (-1.001) ValueO: Select Ceil (-1.001) value from dual 3. Round (small)S: Select floor (-1.001) ValueO:

  In database operations, I often encounter the problem of using random numbers. A few days ago, Xiang Ge asked me about SQL Server's batch generation of random numbers. I remember that he also asked me questions about random numbers under oracle,

A constant The definition of a constant must include the keyword constant. Example: zero_value constant number: = 0; 2 variables2.1) Declare VariablesVariable_name [constant] databyte [not null] [: = | default expression];Example: V1 varchar2 (25 );

Varchar2 () Storage character, variable length, maximum length, maximum 4000 bytes Number Store numbers Date Storage date Char () Storage character, fixed length (if a data is shorter than the definition length,

I write this post is just to make a summary of a point met this week. If not, ask friends in the garden to give more comments. During this week's work, you need to add a function to pakage. This function requires dynamic SQL organization, To

Use of any, some, and all, and nested queries for cross-operation variance operations (Oracle) Select EMP. empno, EMP. ename, EMP. Job, EMP. Sal from Scott. EMPWhere SAL> Any (select Sal from Scott. EMP where job = 'manager '); -- As long as SAL>

. Net connection to the Oracle database currently has three methods: 1. oledb, which requires you to install the Oracle client. I have used this method for Oracle databases over the past two years. Although the connection speed is a little slower,

1. What is ODF. Ne ,? Oracle specially compiled ORACLE data provider for. Net (ODP. Net), an ORACLE data access API for Microsoft. NET environment. Http://www.oracle.com/technetwork/cn/testcontent/o23odp-084525-zhs.html for the official code, does

1. Whether a table exists under the current userSelect count (*) from user_tables where table_name ='Table_name';Note: In general, the table_name in the quotation marks must be in uppercase.If the result is 1, The table exists. If the result is 0,

--------------------------------------------------------------------------- ------------------- Create or replace package packtest As Type string_array is table of varchar2 (21) index by binary_integer; Type int_array is table of number (4) index by

This article describes the concepts and operations of partition tables from the following aspects: 1. table space and Partition Table concept 2. table Partition Function 3. advantages and disadvantages of Table Partitioning 4. table partition types

1. Select deptno, row_number () over (partition by deptno order by SAL) from EMP order by deptno; 2. Select deptno, rank () over (partition by deptno order by SAL) from EMP order by deptno; 3. Select deptno, dense_rank () over (partition by deptno

3.1 Definition of Objects Objects can be nested, and the number of nested levels is not limited. 1. routine: -- Create an object header Create or replace type test_obj is object ( M_name varchar2 (30 ), M_id number, Member procedure getname (p_id in

Transaction 6.1 A transaction is a logical unit of work. It consists of one or more data control statements (DML) or data definition statements (DDL. Oracle provides two Common transactions: Read-only transactions and read/write transactions. Read-

There are two ways to execute dynamic SQL: dbms_ SQL package and local dynamic SQL. 7.1 dbms_ SQL package Powerful functions and a large number of functions are rarely used. 7.2 local dynamic SQL 7.2.1 execute DDL statements Begin Advanced PL/SQL

The dbms_output package is a package that can be displayed on the screen using SQL * Plus. The utl_file is a server-side built-in read/write file. Package, which can read and write data on the server side. text_io is a client read/write package