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
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
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
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
Query
The SELECT statement is used to query data from the database. When the SELECT statement is used in PL/SQL, it must be used with the INTO clause. The return value of the query is assigned to the variable in the INTO clause, variable
PL/SQL cursor usage, plsql cursor usageZookeeper
Use of cursors
① Cursor ConceptTo process SQL statements, ORACLE must allocate a region called context area to process required information,This includes the number of rows to be processed, a pointer
SQL is the language used to access the Oracle database. PL/SQL expands and enhances SQL functions. It also introduces stronger
Program Logic. PL/SQL supports DML commands and SQL transaction control statements. DDL is not supported in PL/SQL, which
SQL is the language used to access the Oracle database. PL/SQL expands and enhances SQL functions. It also introduces stronger
Program Logic. PL/SQL supports DML commands and SQL transaction control statements. DDL is not supported in PL/SQL, which
Query
The SELECT statement is used to query data from the database. When the SELECT statement is used in PL/SQL, it must be used with the into clause. The return value of the query is assigned to the variable in the into clause, variable declaration
1, what is a cursor.① retrieves a result set from a table from which the mechanism for interacting with each record is pointed.Operations in the ② relational database are performed on a complete rowset.The rowset returned by the SELECT statement
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