Syntax (call model method) –Create a User. php file in application/controllers directory. Load above created Main_model using $this->load->model('Main_model') method in the __construct() method and call getUsers() method using $this->Main_model->getUsers() . Store the return response in a $data variable.
Use the below query to display the query string: print_r($this->db->last_query()); To display the query result follow this: print_r($query);
result_array()This function returns the query result as a pure array, or an empty array when no result is produced. Typically you'll use this in a foreach loop, like this: $query = $this->db->query("YOUR QUERY");
try { // do database connection } catch (Exception $e) { // DO whatever you want with the $e data, it has a default __toString() so just echo $e if you want errors or default it to connect another db, etc. echo $e->getMessage(); // Connect to secondary DB. }
How to retrieve data from Database in HTML form?
- Step 1: Connection with Database. The dbConn. php file is used to make a connection with the database. The dbConn. php is a common file which is connected with MySQL database.
- Step 2: Fetch or retrieve data from Database. This all_records. php file is used to display records from the database. We are using dbConn.
CodeIgniter RocksCodeIgniter is a powerful PHP framework with a very small footprint, built for developers who need a simple and elegant toolkit to create full-featured web applications.
How to Pass Data From Controller to View in CodeIgniter
- Create a View.
- Load the View.
- Pass array from the controller to view.
- Load Multiple Views.
- Sort Views in Subfolders.
- Add Dynamic Data to Views.
- Create the Loops.
- Returning View as Data.
php $db = new database(); $query = "select * from data"; $result = $db->select($query); echo "<table>"; echo "<tr>"; echo "<th>Name </th>"; echo "<th>Roll </th>"; echo "</tr>"; while($row = mysqli_fetch_array($result)) { echo "<tr>"; echo "<td> $row[name]</td>"; echo "<td> $row[roll]</td>"; echo "</tr>"; } echo "</
Within the WHERE clause lies many possibilities for modifying your SQL statement. Among these possibilities are the EXISTS, UNIQUE, DISTINCT, and OVERLAPS predicates. Here are some examples of how to use these in your SQL statements.
You can use union : select id_product from tb_compare union select id_product from tb_product_field; Note that union removes duplicate rows in a list, so distinct is not necessary. In this case, a row consists only of a single value.
Below are alternate solutions :
- Remove Duplicates Using Row_Number. WITH CTE (Col1, Col2, Col3, DuplicateCount) AS ( SELECT Col1, Col2, Col3, ROW_NUMBER() OVER(PARTITION BY Col1, Col2, Col3 ORDER BY Col1) AS DuplicateCount FROM MyTable ) SELECT * from CTE Where DuplicateCount = 1.
- Remove Duplicates using group By.
Unique was the old syntax while Distinct is the new syntax,which is now the Standard sql. Unique creates a constraint that all values to be inserted must be different from the others. Distinct results in the removal of the duplicate rows while retrieving data.
The DISTINCT keyword is applied to all columns. It means that the query will use the combination of values in all columns to evaluate the distinction. If you want to select distinct values of some columns in the select list, you should use the GROUP BY clause.
DISTINCT can be also used on multiple columns at once; in that case it will evaluate the duplicates based on the combination of values of those columns. DISTINCT behavior can be simulated by GROUP BY clause.
You can use CTE to get the distinct values of the second table, and then join that with the first table. You also need to get the distinct values based on LastName column. You do this with a Row_Number() partitioned by the LastName, and sorted by the FirstName.
Theoretically, there is no upper limit on the number of tables that can be joined using a SELECT statement. (One join condition always combines two tables!) However, the Database Engine has an implementation restriction: the maximum number of tables that can be joined in a SELECT statement is 64.
In SQL, to fetch data from multiple tables, the join operator is used. The join operator adds or removes rows in the virtual table that is used by SQL server to process data before the other steps of the query consume the data.
To count the number of different values that are stored in a given column, you simply need to designate the column you pass in to the COUNT function as DISTINCT . When given a column, COUNT returns the number of values in that column. Combining this with DISTINCT returns only the number of unique (and non-NULL) values.
SQL SELECT DISTINCT StatementSELECT DISTINCT returns only distinct (i.e. different) values. The DISTINCT keyword eliminates duplicate records from the results. DISTINCT can be used with aggregates: COUNT, AVG, MAX, etc. It operates on a single column.
You can use CTE to get the distinct values of the second table, and then join that with the first table. You also need to get the distinct values based on LastName column. You do this with a Row_Number() partitioned by the LastName, and sorted by the FirstName.
distinct, separate, discrete mean not being each and every one the same. distinct indicates that something is distinguished by the mind or eye as being apart or different from others. two distinct versions separate often stresses lack of connection or a difference in identity between two things.
The go to solution for removing duplicate rows from your result sets is to include the distinct keyword in your select statement. It tells the query engine to remove duplicates to produce a result set in which every row is unique.
To select duplicate values, you need to create groups of rows with the same values and then select the groups with counts greater than one. You can achieve that by using GROUP BY and a HAVING clause.
Filter for unique values or remove duplicate values
- To filter for unique values, click Data > Sort & Filter > Advanced.
- To remove duplicate values, click Data > Data Tools > Remove Duplicates.
- To highlight unique or duplicate values, use the Conditional Formatting command in the Style group on the Home tab.
