open cursor for select in oracle example

Oracle Database: PL/SQL cursor overview, oracleplI. cursor Concept Literally, it refers to a swimming cursor, which is a handle or pointer pointing to the context area. When performing the CRUD operation in the PL/SQL block, ORACLE allocates a

Today, we will briefly summarize the usage of cursor in PL/SQL. Cursor category: -- Explicit cursor-- Static cursor | | -- Implicit cursorCursor |-- Strong type (Restriction), specifying the return type-- Dynamic Cursor -- ref cursor |-- Weak type

The concept of cursors: A cursor is a memory workspace of SQL that is defined by the system or user as a variable. The role of a cursor is to temporarily store blocks of data that are extracted from the database. In some cases, the data needs to be

There are two types of cursors in Oracle: an explicit cursor, an implicit cursor. A display cursor is a cursor defined with the cursor...is command that handles multiple records returned by a query statement (SELECT), while an implicit cursor is a

Basic Oracle cursor and basic oracle cursor I. cursorThe cursor is used to process the multi-row records retrieved from the database (using the SELECT statement ). With the cursor, the program can process and traverse the entire record set returned

1. What is a cursor?① Retrieve the result set from the table and point to a record for interaction at a time.② Operations in relational databases are performed on the complete set of rows.The row set returned by the SELECT statement includes all

1, what is a cursor? ① retrieves the result set from the table, and the mechanism from which each point points to a record for interaction.The operations in the ② relational database are performed on the complete rowset.The rowset returned by the

1. Cursor conceptLiterally, it refers to a swimming cursor, which is a handle or pointer pointing to the context area.When performing the CRUD operation in the PL/SQL block, ORACLE allocates a context zone for it in the memory. The database language

Problems encountered at work: 1. There is a custom dictionary table: mdl_class_js This table stores the names of many other tables (called resource tables). (In the mdl_class_js table, fields: table_name are used to represent these resource

Detailed description of Oracle CURSOR instance, oraclecursor CURSORI,Cursor Overview Cursor is a data buffer provided by the database system in the memory. It stores the execution results of SQL statements. Each cursor has a name. You can use SQL