Learn how to use prepared sql statements in prodigyview.

1. Prepared Statements

2. Overview
Objectives
Learn the basics of creating, updating, searching, and
deleting data with prepared statements.
Requirements
 A database connection
 A basic understanding of how to write queries
Estimated Time
8 minutes

3. Follow Along With Code
Example
1. Download a copy of the example code at
www.prodigyview.com/source.
2. Install the system in an environment you feel
comfortable testing in.
3. Proceed to
examples/database/PeparedStatements.php

4. Prepared Statements Defined
If you are new to prepared statements, you are probably
wondering what they are. The simple explanation they
can described as is cached sql statement that can be
reused multiple times. Prepared statements have
advantages to them.
1. No SQL Injection: The driver handles sanitizing
values passed. Variables in a prepared statement will
not cause SQL injection.
2. Faster Queries: Because the sql statements are
saved, they do not have to
analyzed/compiled/optimized every time, making
execution faster in certain situations. They are not
the magic bullet.

5. Prepared Insert
Let’s begin by first inserting data into the database. We
need to have a table to insert into and data to insert.
1. Data to be inserted, column – value format
2. Name of the table to insert 3. Name of the column that is auto
data into incremented

6. Prepared Insert Explain
In our previous example, we are inserting a query and returning
the auto generated id. The method used for that looks and
operates like below:
 $table_name: The table the query is going into
 $returnField: The field that is going to be returned. Used for Postgresql.
 $returnTable: The table that contains the field that the auto-generated will be
returned from. Used for MS SQL.
 $data: Data to be inserted into the table using column => value format
 $formats: Optional. By default is an empty row, but is associated with the
values passed. So if the value at $data[0] is a string, the $format[0] should be
‘s’ for string.

7. Prepared Select
Now with a prepared select, there is not a complex method that
handles placing the placeholders for us yet. For now, the place
holders have to be placed manually.
1. Write the select statement 2. Set the Place Holder
3. Set the data to be updated 4. Execute the update query

8. Prepared Select Explained
The placeholder’s method puts a placeholder that
corresponds with a variable. The place holder also
increments with every variable in the query.
This means that if $data had 2 more variables, then those
variables should match a variable in the query and they
should be: getPreparedPlacholder(2) for the second
variable and getPreparedPlacholder(3) for the third.

9. Prepared Update
So we are going to need to update records. We need the table
to be updated, the data that is going updated, and what values
to look for when updating the date.
1. Set the data to be updated 2. Update where these values are found
3. Set the table to update 4. Data to be updated 5. Where to update

10. Prepared Update Explained
The prepared update requires two list.
Data List
The data list contains the values you are updating. They
should be in the array in a column => value format. The
array key is the column name to update, and the value is
the value to go in that column.
Where List
The where list defines the portion of the where clause in
the sql statement. These values determine what row(s)
will be updated.

11. Prepared Delete
And the final prepared statement is the prepared delete. I
think by now you get the idea of the $table and the
$wherelist.

12. Review
1. Insert data into a table and return the generated id with
PVDatabase::preparedReturnLastInsert(); method
2. Search for data with PVDatabase::preparedSelect();
method
3. Update data with PVDatabase::preparedUpdate();
method
4. Delete data with PVDatabase::preparedDelete();
method

13. API Reference
For a better understanding of the database, visit the api
by clicking on the link below.
PVDatabase
More Tutorials
For more tutorials, please visit:
http://www.prodigyview.com/tutorials
www.prodigyview.com