oracle connect by prior

Oracle "connect by" is a hierarchical query clause, which is generally used for tree or hierarchical query of result sets. Its syntax is: [ START WITHcondition ]CONNECT BY [ NOCYCLE ] condition The start with .. connect by clause can be used to select data that has a hierarchical relationship (usually some sort of pa

Tags: rom here ott from dead loop select name log withIf the table contains hierarchical data, you can use hierarchical query clauses to select row-level order.1. Hierarchical query clause syntaxHierarchical query clause syntax: {CONNECT by [nocycle] condition [and condition] ... [START with condition]| START with Condition CONNECT by [nocycle] condition [and condition] ...} START with: Specifies the node

1. Basic Grammar SELECT * from table [start and condition] connect by [prior] Id=parentidIt is commonly used to find data that has a parent-child relationship, that is, a tree-structured data, and its return data can clearly differentiate each layer of data. The start with condition is used to limit the first layer of data, or to call the root node data, to find the second tier of data based on this p

placed.Environment.SetEnvironmentVariable("PATH", oraclePath,EnvironmentVariableTarget.Process);This sentence sets the environment variable "PATH", writes the folder where the Oracle driver resides, and the third parameter indicates that the PATH only works in the current process and does not modify the computer itself. Note: If you use some external programs, there are other path variables to set up, join here. See. NET related documentation for spe

Tags: oracle-11g navicat win7-64bitNavicat for Oracle Connect Oracle 11G operation Flow 1 Changing the Oracle configuration file After you install Oracle 11g, you need to change the Listener.ora and Tnsnames.ora two files under th

Ali Electric Surface asked the relevant knowledge, find this article on the Internet. These keywords are query recursive data, forming a tree-like structure. Only Oracle support is available, and other data is implemented in conjunction with stored procedures Grammar: SELECT * FROM Some_table [Where Condition 1] Connect by [Condition 2] Start with [condition 3]; The order in which the

Tags: ROM editor development targe data Common password color sizeBrief introduction:It is also quite common that we often encounter the need to connect to an Oracle database when we develop our application scenarios. So so. NET environment is connected to an Oracle database and can be tns/sql.net through a configuration file, and TNS must be an

Toad How to connect Oracle without Oracle ClientThe original connection to Oracle is always installed Oracle client, it is very troublesome, on the one hand to bring the Oracle disk, on the other hand, it is very uncomfortable to

Label:64-bit operating system how to use Plsql to connect remote or local Oracle data in the case of locally installed Oracle databasesCurrently Plsql only supports 32-bit Oracle clients, how can I use Plsql to connect data with a 64-bit

handCONNECT_BY_ISLEAFThe value is 0, indicating that the child component to be retrieved still exists. Skip Loop As long as you use hierarchical data for work, you may encounter a cyclical hierarchy. For example, someone may set the parent component of a car as a spark plug: UPDATE bill_of_materialsSET parent_assembly = 113WHERE assembly_id=100; An attempt to query "Automobile" in the component tree will fail now: SELECT RPAD(' ', 2*(LEVEL-1)) || assembly_name assembly_name,quantityFROM bi