how to show all tables in oracle

Because the MySQL database has been used, today just a whim, thinking and Java are the same boss out of Oracle himself will not, say go will not be a bit embarrassing, so began to turn data, watching video to get up, step by step, think about what to write, start from the creation of the table, OK, It's not a lot to talk about. Create a table:User table:CREATE TABLE User (ID Number (5,0) NOT null primary key auto_increment,DeptID Number (5,0) is not N

Label:Oracle takes the intersection of data from two tablesKeyword: Oracle takes the intersection of data from two tables INTERSECTOracle, as a large relational database, often needs to extract the intersection data of two tables in daily applications.For example, the following table is required to find the salary 2500 (excluding 2500) and the male (M) employee n

OracleFaq (how to change the column name and sequence of the table in ORACLE). If you need to reprint it, please indicate the source! Anyone who has used ORACLE knows that it is very cumbersome to change the column name and sequence of tables in ORACLE. here is a simple method. SQL> select object_id from all_objects w

know that the optimal hash join occurs when we can put the entire hash table in memory, so that all join operations can be done in memory, which is our ideal pattern. However, when our memory is unable to drop the entire hash table, we have to hash join in OnePass mode.1. First, because memory can not put down all the hash table content, it will result in some hash bucket in memory, some hash bucket on dis

the function of setting unused is to make the CPU, memory and other resources insufficient, Do the UNUSED tag and wait until the database resource is idle with the drop UNUSED columns Delete. 3. Delete tables (drop table) DROP table table [PURGE]; When you delete a table, the database loses all of the data in the table, and all its associated indexes are deleted

An example of the row-to-column and column-to-Row Operations in Oracle Data Tables. Row-to-ColumnOne table The query result is -- Row-to-column Conversion select years,(select amount from Tb_Amount as A where month=1 and A.years=Tb_Amount.years)as m1,(select amount from Tb_Amount as A where month=2 and A.years=Tb_Amount.years)as m2,(select amount from Tb_Amount as A where month=3 and A.years=Tb_Amount.yea

During the interview, some companies asked ORACLE about the development shortcomings? I didn't understand it at the time. Recently, I think that is the use of UPDATE and temporary tables. Originally, I wanted to generate statistical data for a table. The table structure is as follows: Weekly, weekly, store, visitors, number of buyers, number of visitors, and number of buyers. 200928, Monday, women's cloth

I used to have an idea that I just wanted to create an index on one or a few of these partitions, and that the other partitions didn't want to be created, and neither the local nor global index was able to achieve that requirement, but the partial Global was introduced from Oracle 12C /local Indexes for partitioned tables solves the problem by creating a local index or global index on the specified partitio

Problem: In Oracle, how does one combine two tables with different rows into one table? SQL: Select s. stagename sname, Sum (nworkhours) nworkhours, Sum (OVERHOURS) OVERHOURS, Sum (nworkhours + OVERHOURS) From T_WorkDetails w, T_stage s Where w. stageid = s. stageid and w. p

("null", "%", "%", new string[] {"TABLE"});List tablenamelist=NewArrayList (); while(Rs.next ()) {Tablenamelist.add (rs.getstring ("TABLE_NAME"));}returntablenamelist;}//Gets the column names of all columns in the data table and adds them to the list structure. PublicList getcolumnnamelist (Connection conn, String TableName)throwsSQLException {DatabaseMetaData Dbmd=Conn.getmetadata (); ResultSet RS= Dbmd.getcolumns (NULL, "%", tableName, "%"); List

?--Error notation: SELECT * FROM student where birthday = null;--Correct notation: SELECT * from student where birthday is null;--If you want to query birthday NOT NULL, you should write this:SELECT * FROM student where birthday are NOT null; --Modify data--Modify a fieldUpdate student Set sex = ' female ' where xh = ' a001 ';--Modify multiple fieldsUpdate student Set sex = ' male ', birthday = ' 1984-04-01 ' where xh = ' a001 ';--Modify data that contains null valuesDo not use = null but use i

Common Oracle Data Dictionary tables view the default tablespace of the current user SQL> select username, default_tablespace from user_users; View the role of the current userSQL> select * From user_role_privs; View the system and table-level permissions of the current userSQL> select * From user_sys_privs;SQL> select * From user_tab_privs; View All

The ORACLE tutorial is: how to determine the repeated records of Oracle database tables. As an Oracle database developer or DBA, you will often encounter this problem in practice: when trying to create a unique index for a column or several columns in the database table, the system prompts the ORA-01452: you cannot cre

Creating a table in Oracle focuses on the table field type and corresponding constraints. 1. create table statement Createtabletname (Fied1 Type 1, Fied1 type 2, Creating a table in Oracle focuses on the table field type and corresponding constraints. 1. Create table statement Create table tname (Fied1 Type 1, Fied1 type 2, Creating a table in Oracle focuses

The following articles mainly describe the actual operation solution for Oracle to delete user tables. This article mainly uses the actual application code to introduce the actual operation steps, the following describes the specific content of the article. I hope you will gain some benefits after browsing it. 1, Select 'drop table' | table_name | ';' From all_tables Where owner = 'username to be

Oracle database-Common operations directivesView port number DirectivesNetstat–aClear screen:Sql> Clear Scre; SQL> Host CLS;Table SpaceCREATE TABLE Spacesql> Create tablespace tc20 datafile 'e:\tc20_data_dbf' size 20m autoextend on Next 5m maxsize 500m;Querying table space NamesSelect from Dba_data_files order by file_name;Query the name of all tablespace, and the physical file name. Queries from the dat

= Dao.excutedataset (tabinfo). Tables[0];var s = Newtonsoft.Json.JsonConvert.SerializeObject (DT);HttpContext.Current.Response.Write (s);HttpContext.Current.Response.End (); } Protected Hashtable SetInfo (){Hashtable AA = new Hashtable ();Aa. Clear ();foreach (string key in Request.Params.Keys){if (Regex.IsMatch (key)){Match m = Regex.match (key);String g = m.gr

-01119: Create Database file ' F:\ORACLE10G\ORACLEDB\ANSTEEL_TEMP. DBF ' ERRORORA-27040: File creation error, unable to create fileOSD-04002: Unable to open fileo/s-error: (OS 3) The system cannot find the path specified. IMP-00017: Due to ORACLE error 1119, the following statement failed:"CREATE tablespace" Ansteel "BLOCKSIZE 8192 datafile ' F:\ORACLE10G\ORACLEDB""\ansteel. DBF ' SIZE 1350M autoextend on N

Mysql determines whether a table exists before it is created and deletes existing tables if one existsDROP TABLE IF EXISTS Sys_area; CREATE TABLE Sys_area (id varchar) NOT NULL COMMENT ' number ', parent_id varchar (+) NOT null COMMENT ' parent number ', Parent_ids varcha R (a) not null COMMENT ' all parent number ', name varchar (+) NOT null COMMENT ' name ', sort decimal (10,0) NOT null COMMENT ' sort ',

The Oracle tutorial you are looking at is the renaming of the foreign key in the Oracle system table. The foreign key of the table in Oracle is a means to guarantee the referential integrity of the system, while referential integrity refers to the constraint relationship with the principal and subordinate properties that are satisfied by the columns distributed i