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so far we have covered the JDBC template class in considerable detail we have written a few methods that do both data fetching as well as writing data into the database and using these methods that we have explored over here so it should be possible to cover all the scenarios that need to be written when it comes to interacting with the database at least most of the common scenarios should be covered you can write and you can use any query that updates or deletes data as well as inserts of course and you also can execute queries that fetch data from the database where JDBC template is just one of the support classes that's provided by spring and the reason why you would want to use something else is because of some of the limitations of the JDBC template again you can do all these operations but one particularly Mattei ssin of using the JDBC template is that you can have only these question mark placeholders in your queries you cannot have named parameters now what are name parameters well name parameters are a way in which you can actually identify these placeholders that you can put inside the query and the problem with these question mark placeholders is that you will have to move around the you know the parameter locations in case you add additional placeholders for example see I have this query over here which has just one placeholder one question mark placeholder and I'm passing one object array with the first element a circle ID now let's say there was one other placeholder that needs to be added to the query as long as the placeholder comes after this question mark we are fine we just hide additional elements to this object array and it will work fine but then if the question mark comes before the placeholder that's already here then we will have to rearrange the elements in the object array so the new element will probably come before this element which is already there so any changes to the query as long as adding or removing these pino these placeholders are concerned will result in a change in the order in which you supply the values for these placeholders which is a pain if you are dealing with a particularly long query so the advantage of using named placeholders is that you can assign names for these placeholders and then you can say when you're substituting the parameters you can say hey put this value for this variable name and then it just goes to the right position respective of the order wherever the you know the placeholder is in the query so this kind of a named placeholder is not possible to write we're using the JDBC template UBC tablet accepts only these kind of a question mark placeholders so in order to address that there is one other class which supports named placeholders and that's called name parameter JDBC template so let's open that in the spring and in the JDBC jar go to this particular package JDBC core named param so this name param has some support classes for addressing this named parameter so here you see a named parameter JDBC template so this is the class that we will use and will use this in place of the existing JDBC template and in fact the name parameter JDBC template that you are seeing over here actually uses the score class the JDBC template and then adds the same parameter functionality on top of it so all the methods that you've seen over here the JDBC template methods all that we've learned so far still applies but then one additional functionality we can do is use named parameters instead of these questions our parameters so let's have a look at that I'll create a new method over here see you have the insert circle over here so I'll just in fact let me just comment this out we will try to rewrite this using in parameter so I'll just copy the first two lines of code over here okay and now here instead of having these question marks I will use name parameters and the way I use name parameters is by using a colon and then the variable name so I'll call this ID and this parameter will call this colon name so you can have as many parameters as you want just start the variable name with a colon and then give the name to the parameter okay so now I will have to use the name parameter template over here and I do that by declaring the name parameter over here just like I have a JDBC template declaration I will also declare a name parameter template of call this the name parameter JDBC template and I will import this from the same package that we have seen okay now that I've done this I will also have to initialize this just like I've done for the JDBC template and normally you wouldn't be doing both of them in the same class you know you try to either be the JDBC template or the name parameter template just because I'm demonstrating the functionality this code will have both so be same as what I have over here just be a different template that's getting in July so in this particular do class I happen to have two JDBC templates so as you can see the you know the initialization is exactly the same it's just a different class different name but then everything is this is exactly the same now the very in which I use that name parameter to run a circle you know a query which has named parameters are slightly different so what I do here is I use a particular class called sequel parameter source a sequel parameter source is an interface for an object that I can use to pass these parameter sources as a map let me write that and it will probably be a bit more clearer a meter source now a sequel parameter source I call this named parameters so this is something that I'm going to prepare to substitute these values so this is this will have the name parameters will have a value for ID and the value for name and then I will pass this name parameter to the name parameter JDBC template so I will create a new I cannot create a new sequel parameter source because it's an interface I can create one of the implementations of the sequel parameter source one of them being map so a map sequel parameter source is an implementation of the sequel parameter source and this will store these values as maps again a sequel parameter source is the source of values for my named we you know parameter placeholders and then I will have to supply a sequel parameter source when I'm running the query and the various apply a sequel parameter sources by creating an instance of the sequel parameter source since this happens to be an interface I cannot say new sequel parameter source I will have to create one of the implementations of that interface one of them being map which provides these values as a map so I will initialize this I will say ID is the variable and then I will pass the ID circle dot gate ID because they'll have to import both these classes so now this will initialize a map sequel parameter source and it'll assign it to a name parameter so this would work fine if it was just one placeholder value say I had only ID over here just like I have for all the other queries is this one placeholder so for this this would work fine it has the ID placeholder name and then the value assigned to it so it's a single value map and this would work fine I have initialized name parameters but in this query I have two named placeholders I have another placeholder coiled name itself so I need to add this to the map sequel parameter source so I will do that by doing a dot add value and then this has a signature of again param name and value so I will use name and then the value thing circle dot get name okay so now I have a initialized named parameters a sequel parameter source so this needs to be passed to my name parameter JDBC template so let's do that now so I will say named parameter JDBC template dot I will use the same method over here the method that I've use which is an update so I will use the update and here you can see there is this particular signature which takes in sequel as the first parameter and then the sequel parameter source as the second parameter so we have both of them sequel is the one that we prepared over here and then the sequel parameter source is the one that I prepared over here so let's use this so the first parameter being the string sequel second parameter being the named parameters and this should do so now I am passing with the query as well as the parameter substitution to the name parameter JDBC template this should do the execution it actually does the same functionality as what we have seen over here the JDBC template dot update but then here we are using named parameters and States so that's the only thing that's different so now let's save and run this to make sure it does this fine so I will again come in this out and then uncommon this so I will create a new row here I'll call it for fourth circle and then I'm getting the size here before you run make sure that your database is running and here is my database is running a network server mode so we are all set let's execute this there you see the count has become four so we will run one more insert make sure that is getting inserted as well now the count should be five and it is five so this is another way in which we can run queries again this is a limitation of the JDBC template that we've been seeing so far it can accept only these question mark placeholders it cannot accept named placeholders like we have done over here so if you need to use something like this you will have to use the named parameter JDBC template and then of course you need to supply the named parameter values with this particular interface the sequel parameter source can use one of the implementations which is the maps equal parameters which allow us to you know add all these values using a map implementation and then once you have done this all you need to do is pass the sequel as well as this named parameter map to the the same methods whatever we have seen so far we can use the same corresponding methods of the name parameter JDBC template now there is one other template class that I would like to briefly cover in this tutorial well I would just like to mention it in fact because this is something that uses a lot of the things that we have discussed so far in both the JDBC template as well as the name parameter gdb see template now let's say you want to use a JDBC template that allows us to do both both the you know the question mark parameter substitution as well as the name parameter substitution in that case it's actually a bad idea to have put these templates lying around in your dao class this is not a good idea you should have just one JDBC template so in order to do that in order to have the option of using both these types of placeholders you use something called as simple JDBC template now the simple JDBC template is new edition and it uses some of the Java 5 features that have been also newly introduced to spring so you can you know it has options for some methods implementing varargs and auto boxing and things like that so in order to use that all you need to do is instead of using either the JDBC template or the name parameter JDBC template you use simple JDBC template import this now this is from JDBC core simple now this does not have all the methods that you've seen oh that's available in the JDBC template are the name parameters or JDBC template this is kind of like it you know it brings in more commonly used methods and features of both these templates and it's very likely that this should suffice for most of the database interactions that we would write so I'd encourage you to explore this class and use that as much as possible