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Full Discussion: Reference to a const
Top Forums Programming Reference to a const Post 82668 by RishiPahuja on Monday 5th of September 2005 06:20:00 AM
Old 09-05-2005
MySQL

Quote:
Originally Posted by arun.viswanath
Can any one explain how the statement '2' in the following statements is a legal one.

int & ref = 3; // Illegal statement - Compiler error.
const int& ref=3 ; // Compile and executes properly.


Thanks in Advance,
Arun

Arun,

value of '3' is a constant hence it can only be assigned to a const reference. below example will help you to understand better.

likewise say if you have:
int a=3;
int &b = a; //this is perfectly legal
const int &c = a; //this is legal

while if you had
const int a=3;
int &b = a; //illegal because : cannot convert from 'const int' to 'int &'
const int &c = a; //this is legal


rishi
 

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EXECUTE(7)                                                         SQL Commands                                                         EXECUTE(7)

NAME
EXECUTE - execute a prepared statement SYNOPSIS
EXECUTE name [ ( parameter [, ...] ) ] DESCRIPTION
EXECUTE is used to execute a previously prepared statement. Since prepared statements only exist for the duration of a session, the pre- pared statement must have been created by a PREPARE statement executed earlier in the current session. If the PREPARE statement that created the statement specified some parameters, a compatible set of parameters must be passed to the EXECUTE statement, or else an error is raised. Note that (unlike functions) prepared statements are not overloaded based on the type or number of their parameters; the name of a prepared statement must be unique within a database session. For more information on the creation and usage of prepared statements, see PREPARE [prepare(7)]. PARAMETERS
name The name of the prepared statement to execute. parameter The actual value of a parameter to the prepared statement. This must be an expression yielding a value that is compatible with the data type of this parameter, as was determined when the prepared statement was created. OUTPUTS
The command tag returned by EXECUTE is that of the prepared statement, and not EXECUTE. EXAMPLES
Examples are given in the Examples [prepare(7)] section of the PREPARE [prepare(7)] documentation. COMPATIBILITY
The SQL standard includes an EXECUTE statement, but it is only for use in embedded SQL. This version of the EXECUTE statement also uses a somewhat different syntax. SEE ALSO
DEALLOCATE [deallocate(7)], PREPARE [prepare(7)] SQL - Language Statements 2010-05-14 EXECUTE(7)
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