Difference MySQL PostGreSQL

The biggest differences are:

• PostGreSQL is case sensitive
• Command/function
• Dates are stored without format in PostGreSQL
• Round off
• Customised functions

Contents

Upgrading Views from mySQL to PostreSQL

When upgrading from IMSMA^NG 5.08.04 to 6.0, the database views need to be adapted, i.e. changed from mySQL syntax to PostgreSQL syntax. The country focal point is taking care of this. For reference, this section describes the main changes encountered. This can also be used as a tutorial for creating views in PostgreSQL, for IMSMA^NG administrators who were used to creating them in mySQL.

Case sensitivity and column names

PostgreSQL, as opposed to MySQL, is case-sensitive. This means that strings need to be provided in exactly the way they are stored in the database. For example, in the table IMSMAENUM, one out of many values in the column ENUMVALUE is Progress Report, with capital P and capital R. In mySQL it was possible to write:

SELECT *
FROM imsmaenum
WHERE enumvalue = 'progress report'

and still get one row as result. In PostgreSQL, the same query will return no result.

Therefore, a create view statement like this:
mySQL

CREATE OR REPLACE VIEW my_view AS
SELECT ...
FROM imsmaenum, ...
WHERE imsmaenum.enumvalue = 'progress report';

needs to be changed to:
PostgreSQL

CREATE OR REPLACE VIEW my_view AS
SELECT ...
FROM imsmaenum, ...
WHERE imsmaenum.enumvalue = 'Progress Report';

The GROUP BY clause

IF and IFNULL (mySQL) / CASE (PostgreSQL) statements

Date manipulations

CAST AS CHAR utf8 (mySQL)