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PHP : Function Reference : IBM DB2, Cloudscape and Apache Derby Functions : db2_prepare

db2_prepare

Prepares an SQL statement to be executed (PECL ibm_db2:1.0-1.6.2)
resource db2_prepare ( resource connection, string statement [, array options] )

db2_prepare() creates a prepared SQL statement which can include 0 or more parameter markers (? characters) representing parameters for input, output, or input/output. You can pass parameters to the prepared statement using db2_bind_param(), or for input values only, as an array passed to db2_execute().

There are three main advantages to using prepared statements in your application:

  • Performance: when you prepare a statement, the database server creates an optimized access plan for retrieving data with that statement. Subsequently issuing the prepared statement with db2_execute() enables the statements to reuse that access plan and avoids the overhead of dynamically creating a new access plan for every statement you issue.

  • Security: when you prepare a statement, you can include parameter markers for input values. When you execute a prepared statement with input values for placeholders, the database server checks each input value to ensure that the type matches the column definition or parameter definition.

  • Advanced functionality: Parameter markers not only enable you to pass input values to prepared SQL statements, they also enable you to retrieve OUT and INOUT parameters from stored procedures using db2_bind_param().

Parameters

connection

A valid database connection resource variable as returned from db2_connect() or db2_pconnect().

statement

An SQL statement, optionally containing one or more parameter markers..

options

An associative array containing statement options. You can use this parameter to request a scrollable cursor on database servers that support this functionality.

cursor

Passing the DB2_FORWARD_ONLY value requests a forward-only cursor for this SQL statement. This is the default type of cursor, and it is supported by all database servers. It is also much faster than a scrollable cursor.

Passing the DB2_SCROLLABLE value requests a scrollable cursor for this SQL statement. This type of cursor enables you to fetch rows non-sequentially from the database server. However, it is only supported by DB2 servers, and is much slower than forward-only cursors.

Return Values

Returns a statement resource if the SQL statement was successfully parsed and prepared by the database server. Returns FALSE if the database server returned an error. You can determine which error was returned by calling db2_stmt_error() or db2_stmt_errormsg().

Examples

Example 949. Preparing and executing an SQL statement with parameter markers

The following example prepares an INSERT statement that accepts four parameter markers, then iterates over an array of arrays containing the input values to be passed to db2_execute().

<?php
$animals
= array(
   array(
0, 'cat', 'Pook', 3.2),
   array(
1, 'dog', 'Peaches', 12.3),
   array(
2, 'horse', 'Smarty', 350.0),
);

$insert = 'INSERT INTO animals (id, breed, name, weight)
   VALUES (?, ?, ?, ?)'
;
$stmt = db2_prepare($conn, $insert);
if (
$stmt) {
   foreach (
$animals as $animal) {
       
$result = db2_execute($stmt, $animal);
   }
}
?>


Code Examples / Notes » db2_prepare

ndt.db2

if you have the error message : PHP Warning:  db2_prepare() [<a href='function.db2-prepare'>function.db2-prepare</a>]: Statement Prepare Failed in (....)
and cannot display the error message using db2_stmt_errormsg() , then check if your database connection handle is (still) valid


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db2_autocommit
db2_bind_param
db2_client_info
db2_close
db2_column_privileges
db2_columns
db2_commit
db2_conn_error
db2_conn_errormsg
db2_connect
db2_cursor_type
db2_escape_string
db2_exec
db2_execute
db2_fetch_array
db2_fetch_assoc
db2_fetch_both
db2_fetch_object
db2_fetch_row
db2_field_display_size
db2_field_name
db2_field_num
db2_field_precision
db2_field_scale
db2_field_type
db2_field_width
db2_foreign_keys
db2_free_result
db2_free_stmt
db2_get_option
db2_lob_read
db2_next_result
db2_num_fields
db2_num_rows
db2_pconnect
db2_prepare
db2_primary_keys
db2_procedure_columns
db2_procedures
db2_result
db2_rollback
db2_server_info
db2_set_option
db2_special_columns
db2_statistics
db2_stmt_error
db2_stmt_errormsg
db2_table_privileges
db2_tables
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