IT貓撲網(wǎng):您身邊最放心的安全下載站! 最新更新|軟件分類|軟件專題|手機(jī)版|論壇轉(zhuǎn)貼|軟件發(fā)布

您當(dāng)前所在位置: 首頁數(shù)據(jù)庫Oracle → Oracle DDL,DML,DCL,TCL 基礎(chǔ)概念

Oracle DDL,DML,DCL,TCL 基礎(chǔ)概念

時間:2015-06-28 00:00:00 來源:IT貓撲網(wǎng) 作者:網(wǎng)管聯(lián)盟 我要評論(1)

  DDL

  Data Definition Language (DDL) statements are used to define the database structure or schema. Some examples:

  CREATE - to create objects in the database

  ALTER - alters the structure of the database

  DROP - delete objects from the database

  TRUNCATE - remove all records from a table, including all spaces allocated for the records are removed

  COMMENT - add comments to the data dictionary

  RENAME - rename an object

  DML

  Data Manipulation Language (DML) statements are used for managing data within schema objects. Some examples:

  SELECT - retrieve data from the a database

  INSERT - insert data into a table

  UPDATE - updates existing data within a table

  DELETE - deletes all records from a table, the space for the records remain

  MERGE - UPSERT operation (insert or update)

  CALL - call a PL/SQL or Java subprogram

  EXPLAIN PLAN - explain access path to data

  LOCK TABLE - control concurrency

  DCL

  Data Control Language (DCL) statements. Some examples:

  GRANT - gives user's access privileges to database

  REVOKE - withdraw access privileges given with the GRANT command

  TCL

  Transaction Control (TCL) statements are used to manage the changes made by DML statements. It allows statements to be grouped together into logical transactions.

  COMMIT - save work done

  SAVEPOINT - identify a point in a transaction to which you can later roll back

  ROLLBACK - restore database to original since the last COMMIT

  SET TRANSACTION - Change transaction options like isolation level and what rollback segment to use

關(guān)鍵詞標(biāo)簽:Oracle基礎(chǔ)概念

相關(guān)閱讀

文章評論
發(fā)表評論

熱門文章 Oracle中使用alter table來增加,刪除,修改列的語法 Oracle中使用alter table來增加,刪除,修改列的語法 oracle中使用SQL語句修改字段類型-oracle修改SQL語句案例 oracle中使用SQL語句修改字段類型-oracle修改SQL語句案例 誤刪Oracle數(shù)據(jù)庫實(shí)例的控制文件 誤刪Oracle數(shù)據(jù)庫實(shí)例的控制文件 為UNIX服務(wù)器設(shè)置Oracle全文檢索 為UNIX服務(wù)器設(shè)置Oracle全文檢索

相關(guān)下載

    人氣排行 oracle中使用SQL語句修改字段類型-oracle修改SQL語句案例 Oracle中使用alter table來增加,刪除,修改列的語法 ORACLE SQL 判斷字符串是否為數(shù)字的語句 ORACLE和SQL語法區(qū)別歸納(1) oracle grant 授權(quán)語句 ORACLE修改IP地址后如何能夠使用 如何加速Oracle大批量數(shù)據(jù)處理 Oracle刪除表的幾種方法