Oracle

Common oracle database operation statement [SQL] ------------------ SQL statement operation and help ------------------------ -- view the help information of a command help show; -- View all system variable value information show all; www.2cto.com --

Oracle tool: DBV usage 1 defines that oracle Bad blocks can be divided into Physical Bad blocks and logical Bad blocks. Bad block corruption information is similar to: ORA-01578: ORACLE data block corruption upted (file #6, block #11) ORA-01110:

Oracle11g: ORA-12545: connection failure problem because the target host or object does not exist 1. find the oracle installation directory and find the two files tnsnames. ora and listener. ora. Their path is as follows: drive letter: app \

In oracle, the two tables insert values to each other and the table's own insert values have two tables, student and otherStudent, the table information is as follows: SQL> desc studentName Type Nullable Default Comments ---- ------------ ------- ---

Understanding of oracle grant authorization GRANT name GRANT-GRANT a user, a group or all users access permissions grant privilege [,...] ON object [,...] TO {PUBLIC | GROUP group | username} You can enter privilege with the following permissions:

Summary of the use of oracle and mysql: Comparison of the use of oracle and mysql: mysql and ORACLE have not been summarized for a while. Do some difference today: www.2cto.com 1. when using a database after using mysql for a period of time and

The two datasets processed by nested loop connection are called the External loop (that is, the driving data source, driving row soulce) and the internal loop (inner loop ). The External Loop is the left subnode, and the internal loop is the right

The data dictionary provided by Oracle is used to store database information. The data dictionary can be used to understand the internal information of the Oracle database, for example, the table creator, creation time, tablespace, and user access

Oracle set operators union, union all, intersect, and minus go straight to the topic: if we need to display the results of the two select statements as a whole, we need to use the union or union all keyword. Union (or union) is used to display

Oracle spatial converts Geometry to the gml string oracle spatial has a function that converts geometry to gml. The function name is SDO_UTIL.TO_GMLGEOMETRY (geo ).This geo is SDO. Geometry type, but the return value of this function is Clob type

Oracle function (rowid value conversion string) ROWIDTOCHAR (rowid) [function] converts rowid value to varchar2 type [parameter] rowid, fixed parameter [Return] Return the 18-character string www.2cto.com [Example] select rowidtochar (rowid) from

Use of oracle order by and union statements when union operations are used, the sorting statement must be placed at the end of the statement. For example: www.2cto.com can only use order by in the last subquery of union, this order by is for the

Create a tablespace in oracle and assign permissions to users -- create a temporary tablespace create temporary tablespace data_temp tempfile 'd: \ oracle \ oraudata \ data_temp.dbf 'size 2000 m autoextend on next 500 m extent management local; www.2

The SQL statement used by oracle to add fields to a table is written in the SQL code www.2cto.com alter table TAB_SMS_BLACKLIST add (BLACK_TYPE NUMBER default 1 not null, COMPANY_ID NUMBER, BLACK_NAME VARCHAR2 (64 )); comment on column

Oracle number syntax and number syntax are very simple: number (p, s) p, s are optional, if not filled, p is 38 by default, s is-48 ~ by default ~ 127. 1. precision, or the total number of digits. By default, the precision is 38 BITs and the value

Oracle EXPLAIN & execution plan explain plan statement explain plan is used to display the execution PLAN selected by the optimizer for the SQL statement. It should be noted that when you get the explain Plan output, you actually get the expected

Oracle 11g login Database control Problem oracle11g login Database control Implementation OEM login encountered the following problems: Error emctl when starting Database Control. bat start dbconsole www.2cto.com windows solution: 1. run cmd and

Create or replace procedure sort_node www.2cto.com (node_xlid in varchar2) as v_start_node varchar2 (100); v_node1 varchar2 (100); v_node2 varchar2 (100); v_count number: = 0; v_index number: = 0; type start_nodes_table is table of varchar2 (100)

Oracle insert statement strange performance problem exception statement: www.2cto.com insert into t_i18n values ('com. huawei. support. enterprise. web. page. mySpace. halp. trainingBackList ', 'zh', 'Return', sysdate, 'test1'); no response has been

A new understanding of Oracle indexes first involves Oracle indexes. Www.2cto.com general index B * tree, BitMap index, function index, composite index, reverse index. The common indexes are described here. B * tree indexes are common indexes. The