Result

Lightning Component

Create the component thus:

 <aura:component implements="force:appHostable"
                controller="OpportunitiesTabController">
    
    <aura:attribute name="data" type="Object"/>
    <aura:attribute name="columns" type="List"/>
    
    <aura:handler name="init" value="{! this <}" action="{! c.doInit }"/>
    
    <article class="slds-card slds-p-bottom_x-small">
        
        <div class="slds-card__body slds-card__body_inner">
            
            <div class="slds-m-top_x-small">
                <lightning:button
                                  aura:id="refresh"
                                  label="Refresh"
                                  title="Refresh"
                                  onclick="{!c.doInit}"
                                  />
            </div>
            
            <div class="slds-text-heading_medium slds-m-top_x-small">Opportunities</div>
            <lightning:datatable
                                 columns="{! v.columns }"
                                 data="{! v.data }"
                                 keyField="id"
                                 onrowaction="{! c.handleRowAction }"/>
            
            
        </div>
    </article>
    
</aura:component>
      

JS controller

      
({
	doInit : function(component, event, helper) {
		helper.loadOpportunities(component);
	},
    
    handleRowAction: function (component, event, helper) {
        var action = event.getParam('action');
        var row = event.getParam('row');
        
        switch (action.name) {
            case 'toLowerCase':
                helper.execute(component, row.Id, 'c.toLowerCase');
                break;
            case 'toUpperCase':
                helper.execute(component, row.Id, 'c.toUpperCase');
                break;
                
        }
    },
})
      
    

JS helper

      
({
    execute : function(component, opptyId, method) {
        console.info('executing: '+method + ' oppty id: '+opptyId)
        const action = component.get(method);
        action.setParams({
            opptyId: opptyId
        });
        action.setCallback(this, function(response) {
            const state = response.getState();
            if (state === "SUCCESS") { 
                console.info(method+' done');
                this.loadOpportunities(component);
            }else {
                console.error(" Error: " + JSON.stringify(response.getError()));
                alert(JSON.stringify(response.getError()));
            }
        });
        $A.enqueueAction(action);
    },
    
    loadOpportunities : function(component) {
		console.info('loading opportunities')
        const actions = [{ label: 'To Lower Case', name: 'toLowerCase' },
                        { label: 'To Upper Case', name: 'toUpperCase' }];
       
        
        component.set('v.columns', [
            { label: 'Name', fieldName: 'linkName', type: 'url', 
             typeAttributes:{label:{fieldName: 'Name'}} },
            { label: 'Account', fieldName: 'linkAccount', type: 'url', 
             typeAttributes:{label:{fieldName: 'nameAccount'}} },
            { label: 'Stage Name', fieldName: 'StageName', type: 'text' },
            { label: 'Created Date', fieldName: 'CreatedDate', type: 'datetime' },
            { type: 'action', typeAttributes: { rowActions: actions } }
        ]);
        
        const action = component.get("c.getOpportunities");
        action.setCallback(this, function(response) {
            const state = response.getState();
            if (state === "SUCCESS") {
                console.info(" opportunities loaded");
                const records = response.getReturnValue();
                records.forEach(function(record){
                    record.linkName = '/'+record.Id;
                    
                    if(record.Account){
                        record.linkAccount = '/'+record.AccountId;
                        record.nameAccount = record.Account.Name  
                    } else {
                        record.linkAccount = '/#';
                        record.nameAccount = 'no account';  
                    } 
                    
                });
                component.set('v.data', records);
            }else {
                console.error(" Error: " + JSON.stringify(response.getError()));
            }
        });
        $A.enqueueAction(action);
    },
})
      
    

Apex class controller

      
public class OpportunitiesTabController {
    
    @AuraEnabled
    public static void toLowerCase(Id opptyId){
        try{
            Opportunity opp = [SELECT Id, Name FROM Opportunity WHERE Id = :opptyId];
            opp.Name = opp.Name.toLowerCase();
            update opp;
        }catch(Exception e){
            throw new AuraException(e.getMessage());
        }
        
    }
    
    @AuraEnabled
    public static void toUpperCase(Id opptyId){
        try{
            Opportunity opp = [SELECT Id, Name FROM Opportunity WHERE Id = :opptyId];
            opp.Name = opp.Name.toUpperCase();
            update opp;   
        }catch(Exception e){
            throw new AuraException(e.getMessage());
        }
    }    
    
    
    @AuraEnabled
    public static List<Opportunity> getOpportunities(){
        return [SELECT Id, Name, StageName, CreatedDate, Account.Name, AccountId 
                FROM Opportunity ORDER BY CreatedDate DESC LIMIT 10]; 
    }
}
      
    

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