![]() Let us execute the above created function and see the results. RAISE NOTICE 'OH state pincode %', v_pincode->'OH' RAISE NOTICE 'CA state pincode %', v_pincode->'CA' CREATE OR REPLACE FUNCTION process_orders() RETURNS BOOL Thanks to PostgreSQL’s rich data types such as hstore or json which can be leveraged to perform such mapping.įollowing is a sample code using a json static object. ![]() So, how to approach this requirement ? Let us discuss the approach further.Īssociating or mapping a name or a key to a value If we are able to access the same pincodes based on their keys, then, the lookup will be more powerful. For example, the pincodes (1st and the 3rd elements) are fetched using their Indexes. However, this code has some limitations because we are unable to fetch the values based on their keys. Let us execute the function created above and see the results. RAISE NOTICE '3rd state pincode %', v_pincode RAISE NOTICE '1st state pincode %', v_pincode postgres=> CREATE OR REPLACE FUNCTION process_orders() RETURNS BOOL Here is a sample code to illustrate the above with an example. If we want to access the pincode value of 3rd state, then, we have to pass the index value 3 using v_pincode. Which means, if we want to access the 1st state pincode, then, we can access the value using v_pincode. Here, the v_pincode holds all the values and we can fetch a specific state’s pincode value, by providing an index. We can also initialize the v_pincode array type with a static set of pincode values. Once we declare this variable, then, we can load all the pincode values from a table/view/function into this array. For example, if we want to store a list of PINCODE values, then, we can declare the variable as v_pincode INT. This ARRAY can be either a base or a custom type. PL/pgSQL in PostgreSQL allows us to declare a variable as an ARRAY type. The key can either be of a text or a numeric type that can be mapped to any value type. This association between a key and a value may be referred to as mapping. Associative array is a collection of (key, value) pairs where a key associates to a value. In programming languages, an associative array may either be called a map or a dictionary. □īefore getting to the workarounds, let us understand what is an associative array. To avoid developers from finding it difficult while performing conversions of PL/SQL from Oracle to PostgreSQL, we are writing this blog post to demonstrate the workarounds available with not much of additional programming effort.īy the way, the fact to note after reading this blog post is that, several features you want to observe in PostgreSQL during migrations or Code conversions are available without the need of an additional Enterprise license with PostgreSQL (which could create a vendor lock-in).Īsk us about possibilities with Community PostgreSQL (Open Source) before switching to an Enterprise licensing. ![]() It might get challenging if the variables need to be accessible in the Exception block. While migrating from Oracle to PostgreSQL, most of the developers ask about the options available in Handling Global associative arrays in PostgreSQL.
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