Oracle

1, Long data type is stored in variable-length strings, the maximum length limit is 2GB. 2, for more than a certain length of text, the basic only long type to store, the data dictionary many objects are defined in a long to store. 3, long type is

Complete optimization of Oracle Database in UNIX environment2007-04-19 12:54:02 Author: changelive Browse Number: 14 Text size: " large "" in the "" Small "into the forumToday's optimization has been transformed to the optimization Wait (waits), in

4.3 single-line character function Common Single-line character functions include the following: █lower █upper █initcap █concat █substr █length █instr █trin █replac Below, we introduce them separately by example. LOWER(column name | expression):

Dual is a virtual table that forms the grammar rules for Select, and Oracle guarantees that there will always be a single record in dual. We can use it to do a lot of things as follows: 1, view the current user, you can execute the following

I need a lot of inserting large text when I write an application, but Oracle's CLOB is cumbersome to do, so I didn't choose to use CLOB, but I used the long type in previous versions of Oracle [but the long type has some limitations, You can have

Preface does not remember, Baidu all have. Problem 1: Unable to find dynamic library libsqlplus.so, this library is present under the Lib folder, if there is no wrong version, this problem should be unable to find dynamic link library. On-line

After a period of study, I will now share my experience on the establishment of spatial indexes as follows. If the data is imported from someone else's library, if a space index was previously built, then you need to delete it to establish your own

Creating partitions is a means of database optimization, and range partitioning is one of the table partitions. The key word for creating a range partition is "range", where the data can be distributed according to the range specified by the

How Oracle aggregates multiple-line functions In the BEA forum, see a masterpiece written by an "expert", an SQL statement is Select r.xm, substr (r.csrq,1,4) | | Years ' | | substr (r.csrq,5,2) | | Month ' | | substr (r.csrq,7,2) | | Th ' Csrq,

With Tab as (select T.object_pid, T.mesh, round (x, 8) x, round (y, 8) y, round (z, 3) z , id from had_object_box_pole T, table (Sdo_util. Getvertices (T.geometry)), Tab1 as (select T.object_pid, T.mesh, T.x, T.y, T.z, T.id, COUNT (*) over (

Similar to other database systems, Oracle string concatenation uses the "| |" string concatenation, which is used in the same way as the plus sign "+" in MSSQLServer. For example, execute the following SQL statement: SELECT ' work # for ' | |

The data is based on an Oracle database Scott/tiger the EMP (employee) and dept (departmental) tables under the demo account: CREATE TABLE DEPT ( DEPTNO number (2) NOT null primary key, dname VARCHAR2 (), LOC VARCHAR2 ( ) ) CREATE

Several ways to start Oracle database1, startup Nomount;Non-installation boot, this way startup executable: Rebuild the control file, rebuild the database, read the Init.ora file, start the instance, that is, start the SGA and background process,

definition of the function:CREATE OR REPLACE FUNCTIONFunction_test (PARAMER1inch VARCHAR,--the type of the parameter does not write length PARAMER2 outVARCHAR, PARAMER3inch VARCHAR) RETURN VARCHAR--function to write return valueAs--Indicates the

1, in order to improve the robustness of the stored procedures, avoid running errors, when establishing a stored procedure should contain the exception handling part.2, exception (EXCEPTION) is a PL/SQL identifier, including pre-defined exceptions,

Set up software only the following comments are strange, and the previous software only different, for RAC install and to upgrade a Oracle Database; previously loaded once set up software only, Next time, post it.Only Oracle base, no Oracle

This case database (12.1.0.2) is installed on the file system, so you only need to deinstall the database. Prerequisites: (1) Close the database, shutdown immediate; (2) Turn off monitoring, Lsnrctl stop (3) Finally, deinstall database

Original website: https://baijiahao.baidu.com/s?id=1591207020267646171&wfr=spider&for=pc[[Email protected]~]# fdisk-l (view partition status)Disk/dev/sda:107.4 GB, 107374182400 bytes, 209.7152 million sectorsUnits = Sector of 1 * bytesSector size

Oracle has a high-speed buffering concept, which is to store executed SQL statements, which Oracle does a lot of work when executing SQL statements, such as parsing SQL statements, estimating index utilization, binding variables, reading blocks, and

Oracle Database Composition:Consists of two parts: Oracle database and database instance;A database is a collection of data files, which is the Oracle background process/thread and the shared memory area allocated by the server;Querying the current