PHPPDOStatement object bindpram (), bindvalue (), and bindcolum

Differences between PHPPDOStatement objects bindpram (), bindvalue (), bindcolum PHP PDOStatement objects bindpram (), bindvalue (), and bindcolumn

PDOStatement: bindParam-bind a parameter to the specified variable name.

Bind a PHP variable to the corresponding name placeholder or question mark placeholder in the SQL statement used for preprocessing. Unlike PDOStatement: bindValue (), this variable is bound as a reference and takes its value only when PDOStatement: execute () is called.

PDOStatement: bindValue-binds a value to a parameter.

Bind a value to the corresponding name placeholder or question mark placeholder in the SQL statement used for preprocessing.

 Prepare ("select * from users where user =: user"); $ user = "jack"; // correct $ stm-> bindParam (": user", $ user ); // error $ stm-> bindParam (": user", "jack"); // correct $ stm-> bindValue (": user", $ user ); // correct $ stm-> bindValue (": user", "jack"); // therefore, bindParam is the second parameter. only the variable name can be used, but not the variable value, bindValue can use specific values.?>

PDOStatement: bindColumn-bind a column to a PHP variable.

Bind a specific variable to a specified column in a query result set. Every call to PDOStatement: fetch () or PDOStatement: fetchAll () will update all the variables bound to the column.

 Prepare ($ SQL); $ stmt-> execute ();/* bind a column number */$ stmt-> bindColumn (1, $ name ); $ stmt-> bindColumn (2, $ color);/* bind by column name */$ stmt-> bindColumn ('calories ', $ cals ); while ($ row = $ stmt-> fetch (PDO: FETCH_BOUND) {$ data = $ name. "\ t ". $ color. "\ t ". $ cals. "\ n"; print $ data ;}} catch (PDOException $ e) {print $ e-> getMessage () ;}} readData ($ dbh);?>

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Differences between PHP PDOStatement objects bindpram (), bindvalue (), and bindcolumn
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