Original: http://ntk2006.blog.sohu.com/135331235.html
Cursor ConceptCursors provide a flexible way to retrieve and operate data from tables. cursors are mainly used on servers to process SQL statements sent from clients to servers, or data
I. cursor Recognition
Cursor allows you to access the result set returned by SQL Server row by row.A major reason for using cursor is to convert the set operation into a single record processing method.After retrieving data from a database using
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
CursorA cursor is a data buffer opened by the system for the user, which holds the results of the SQL statement execution. Each cursor area has a name that allows the user to retrieve the record from the cursor one at a-and assign it to the main
Cursor and dynamic SQL, cursor dynamic SQL
Cursor type: Static cursor (the cursor is statically bound to a select statement during compilation. This cursor can only act on one query statement) and dynamic cursors (that is, we want our query
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
During database development, when the data you retrieve is only one record, the transaction statements you writeCodeSelect Insert statements are usually used. However, we often encounter this situation, that is, reading a record from a result set
-In Oracle, when we execute a SELECT statement from Pl/sql, the Oracle RDBMS (relational database management system) assigns a private SQL zone to the SGA shared pool for that statement.
--At the same time, put the query result set into the system
Cursor is a method for processing data. To view or process data in a result set, A cursor provides the ability to forward or backward data in a result set by one or more rows. We can use a cursor as a pointer, which can specify any position in the
A major reason for using cursor is to convert the set operation into a single record processing method. After retrieving data from a database using SQL, the results are stored in a memory area, and the results are often a collection containing
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