### Genero BDL: Defining and Generating Reports

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Explains the structure of Genero BDL reports, including the DEFINE, ORDER BY, and FORMAT sections, and provides an example of a customer report.

```BDL
-- Example: Customer Report Definition
REPORT CustomerReport
  DEFINE
    -- Define variables and fields here
    v_customer_name string
  ENDDEFINE
  
  ORDER BY name
  
  FORMAT
    -- Define the report layout and content
    PAGE HEADER
      PRINT "Customer Report"
    ENDPAGE HEADER
    
    DETAIL
      PRINT customer_id, name, email
    ENDDETAIL
    
    PAGE TRAILER
      PRINT "Page " + page_number
    ENDPAGE TRAILER
  ENDFORMAT
ENDREPORT

```

--------------------------------

### Genero BDL: Enhancing Forms with Toolbars and Menus

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Provides examples of how to add interactive elements like toolbars and top menus to Genero forms, improving user interface and navigation.

```BDL
-- Example: custform.per (Adding a Toolbar)
TOOLBAR
  BUTTON "New" ACTION new_customer
  BUTTON "Save" ACTION save_customer
ENDTOOLBAR

-- Example: custform.per (Adding a Topmenu)
TOPMENU
  MENU "File"
    ITEM "Open" ACTION open_file
    ITEM "Save" ACTION save_file
    SEPARATOR
    ITEM "Exit" ACTION exit_program
  ENDMENU
ENDTOPMENU

```

--------------------------------

### Genero BDL: Implementing Query-by-Example

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Details the implementation of a Query-by-Example feature in Genero BDL, including steps for constructing SQL statements and handling user input for query criteria.

```BDL
-- Example module: custquery.4gl (Function get_cust_cnt)
function get_cust_cnt() returns integer
  define v_count integer
  
  -- Construct the SQL statement based on user input
  construct v_sql_query from "select count(*) from customers where name like ?"
  prepare stm from v_sql_query
  execute stm using v_customer_name
  fetch stm into v_count
  
  return v_count
end function

```

--------------------------------

### Genero BDL: Connecting to a Database

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Illustrates how to establish a connection to a database using Genero BDL. This program is essential for data-driven applications.

```BDL
program connectdb

  -- Connect to the database (e.g., using connection string)
  connect to database 'mydatabase' user 'myuser' password 'mypass'

  if status = 0 then
    display "Successfully connected to the database."
  else
    display "Failed to connect to the database."
  end if

  -- Disconnect from the database
  disconnect

end program

```

--------------------------------

### Genero BDL: Compiling and Executing a Simple Program

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Demonstrates the process of compiling and executing a basic Genero BDL program. This is a foundational step for any BDL development.

```BDL
program simple_program

main
  display "Hello, Genero!"
end program

```

--------------------------------

### Genero BDL: Using Cursors for Data Retrieval

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Explains how to use cursors in Genero BDL to fetch data from the database row by row. This is crucial for processing large result sets efficiently.

```BDL
-- Example module: custquery.4gl (function cust_select)
function cust_select()
  declare c_customer cursor for select customer_id, name, email from customers
  
  open c_customer
  -- Process rows using fetch
  fetch c_customer into v_cust_id, v_cust_name, v_cust_email
  while SQLCODE = 0
    -- Process the fetched row
    fetch c_customer into v_cust_id, v_cust_name, v_cust_email
  end while
  close c_customer
end function

```

--------------------------------

### Genero BDL: Error Handling with WHENEVER ERROR

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Demonstrates how to implement robust error handling in Genero BDL using the WHENEVER ERROR statement to manage database errors and exceptions.

```BDL
program error_handling

  -- Define error handling block
  whenever error
    display "An error occurred: " + SQLERRMESSAGE
    -- Close cursor if open
    if cursor_is_open(c_mycursor) then
      close c_mycursor
    end if
    -- Exit program or perform other error recovery
    exit program
  end whenever

  -- Database operations that might cause errors
  -- ...

end program

```

--------------------------------

### Genero BDL: Displaying Data in Screen Arrays (TABLE)

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Explains how to use screen arrays and TABLE containers in Genero BDL forms to display multiple rows of data, enhancing the presentation of tabular information.

```BDL
-- Example: manycust.per (Form definition with TABLE)
FORM
  -- ... other form elements ...
  TABLE many_customers
    COLUMNS 3
    WIDTH 100
    ROW HEIGHT 1
    HEADER "ID", "Name", "Email"
    DATA customer_id, name, email
  ENDTABLE
  -- ... other form elements ...
ENDFORM

```

```BDL
-- Example Library module: cust_lib.4gl (Loading the Array)
function load_customer_array()
  define v_cust_record like customers.*
  define i integer
  
  -- Clear the array before loading
  remove many_customers.*
  
  -- Fetch data and populate the array
  foreach v_cust_record in customers
    let i = i + 1
    let many_customers[i].customer_id = v_cust_record.customer_id
    let many_customers[i].name = v_cust_record.name
    let many_customers[i].email = v_cust_record.email
  end foreach
end function

```

--------------------------------

### Genero BDL: Retrieving and Displaying Customer Data

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Shows how to retrieve customer data from a database and display it in a window using Genero BDL. It involves opening windows, interacting with the user, and querying data.

```BDL
program dispcust

  -- Open the main window and the customer form
  open window 1 from "custform.per"
  open form 1.1 from "custform.per"

  -- Retrieve and display customer data
  query cust.*
  display cust.*

  -- Handle user interaction (e.g., closing the form)
  accept
  close form 1.1
  close window 1

end program

```

--------------------------------

### Genero BDL: Adding, Updating, and Deleting Records

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Covers the essential operations of adding new records, updating existing ones, and deleting records from database tables using Genero BDL's INPUT and SQL statements.

```BDL
-- Example: Module custquery.4gl (function insert_cust)
function insert_cust(v_cust_id integer, v_name string, v_email string)
  -- Insert a new customer record
  insert into customers (customer_id, name, email)
  values (v_cust_id, v_name, v_email)
end function

-- Example: Module custquery.4gl (function update_cust)
function update_cust(v_cust_id integer, v_name string, v_email string)
  -- Update an existing customer record
  update customers set name = v_name, email = v_email
  where customer_id = v_cust_id
end function

-- Example: Deleting a Row
-- ... SQL DELETE statement ...

```

--------------------------------

### Genero BDL: Array Input for Data Modification

Source: https://4js.com/online_documentation/fjs-genero-3.21.09-manual-tutorial-html

Details the INPUT ARRAY statement in Genero BDL, allowing users to efficiently input and modify multiple records displayed in a screen array.

```BDL
-- Example: Function inparr_custall in custquery.4gl
function inparr_custall()
  -- Input data into the screen array
  input array many_customers
  
  -- Process changes after input
  if status = 0 then
    call store_num_ok()
  end if
end function

```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.