Posts (page 6)
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4 min readIn PostgreSQL, you can combine two queries using the UNION operator. The UNION operator is used to combine the result sets of two or more SELECT statements into a single result set.To combine two queries, you need to make sure that both queries return the same number of columns and that the data types of the corresponding columns match. You can also use the UNION ALL operator if you want to include duplicate rows in the result set.
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8 min readTo connect PostgreSQL to C++, you can use the libpq library, which is the native C API for PostgreSQL. This library allows you to connect to a PostgreSQL database, send queries, and retrieve results within your C++ code.To get started, you will need to include the libpq library in your C++ project and set up the necessary includes and configurations. You can then use the libpq functions to establish a connection to your PostgreSQL database, execute SQL queries, and handle the query results.
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5 min readTo remove all JSON attributes with a certain value in PostgresQL, you can use the jsonb_set function to update the JSON column and jsonb_strip_nulls function to remove any null attributes that may be left behind after removing the attributes with the specified value. You can achieve this by using a single UPDATE statement with a WHERE condition that checks for the presence of the attribute with the specified value.
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7 min readTo loop a query in PostgreSQL, you can use a PL/pgSQL block with a LOOP construct. Within the loop, you can execute the query and process the results accordingly. You can use a cursor to fetch rows from the query result set and iterate over them. Additionally, you can use variables to control the loop, such as setting a maximum number of iterations or breaking out of the loop based on certain conditions.
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3 min readTo change the value in an array column in PostgreSQL, you can use the array functions provided by PostgreSQL. You can create a new array with the updated value or modify the existing array directly using functions like array_append or array_remove. Additionally, you can update the entire array column with the new value by using the array syntax in the UPDATE statement. Make sure to handle NULL values or empty arrays appropriately while updating the array column.
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4 min readTo set datetime format in form_input in CodeIgniter, you can use the date helper function of CodeIgniter. You can load the date helper in your controller or view by using the following code:$this->load->helper('date');Once the helper is loaded, you can use the mdate function to format the datetime input.
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5 min readIn CodeIgniter, you can generate an auto increment ID manually by using the following steps:First, open your model file where you want to generate the auto increment ID. Add the following code to the constructor of your model to load the database library: $this->load->database(); Next, create a function in your model to generate the auto increment ID.
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4 min readTo crop an image using CodeIgniter, you can use the Image Manipulation Library that comes built-in with the framework. Start by loading the library using the following code:$this->load->library('image_lib');Next, set the configuration options for cropping the image. You can define the source image, crop coordinates (x, y, width, height), and the destination image path.$config['image_library'] = 'gd2'; $config['source_image'] = 'path/to/source/image.
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7 min readIn CodeIgniter, you can call a model function from a view by first loading the model in the controller, and then passing data from the model to the view. This can be done by using the $this->load->model('model_name') function in the controller to load the model and then calling the function from the model in the controller and passing the data to the view using the $this->load->view('view_name', $data) function.
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5 min readTo send an email using Gmail SMTP in CodeIgniter, you first need to set up your Gmail account to allow less secure apps to access it. You can do this by going to your Google account settings and enabling the "Allow less secure apps" option.Once you have done that, you need to configure your CodeIgniter application to send emails using Gmail SMTP. You can do this by editing the config/email.php file in your CodeIgniter application.
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5 min readTo get the CKEditor value in CodeIgniter, you can first capture the value from the CKEditor instance using JavaScript. You can then pass this value to your CodeIgniter controller through an AJAX request or a form submission. In the controller, you can retrieve the value using the input class provided by CodeIgniter. Finally, you can process the value as needed within your CodeIgniter application.
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7 min readTo crop an image using ImageMagick in CodeIgniter, you first need to have ImageMagick installed on your server. Then, you can use the following code to crop the image: $this->load->library('image_lib'); $config['image_library'] = 'imagemagick'; $config['library_path'] = '/usr/bin/convert'; // Path to the ImageMagick executable $config['source_image'] = '/path/to/source/image.