What is the command in sql for data retrieval

<blockquote><p>The command used for data retrieval in SQL is SELECT, and its syntax is SELECT column1, column2, ...FROM table_name WHERE condition. The WHERE clause is used to filter data, using operators and wildcards. Other data retrieval commands include DISTINCT (unique values), GROUP BY (grouping), HAVING (group filtering), and ORDER BY (sorting). </p></blockquote> <p><img src="/static/imghw/default1.png" data-src="https://img.php.cn/upload/article/202405/07/2024050705152471566.jpg" class="lazy" alt="What is the command in sql for data retrieval" ></p> <p><strong>Commands used for data retrieval in SQL</strong></p> <p>SQL (Structured Query Language, Structured Query Language) is A widely used database query language for retrieving, updating, and managing data from databases. Among them, the main command used for data retrieval is <code>SELECT</code>. </p> <p><strong>SELECT Command</strong></p> <p><code>The SELECT</code> command is used to extract specific data from a database table. The basic syntax is as follows: </p><div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:php;toolbar:false;'>SELECT column1, column2, ... FROM table_name WHERE condition</pre><div class="contentsignin">Copy after login</div></div><p> Among them: </p><ul><li><code>column1</code>, <code>column2</code>, etc. specify the columns to be retrieved </li><li> <code>table_name</code>Specify the table from which to retrieve data</li><li><code>condition</code>(Optional) Specify filter conditions to retrieve only rows that meet specific conditions</li></ul> <p><strong>Example</strong></p><p>The following query retrieves the <code>customer_id</code> and <code>name</code> columns for all customers from the <code>customers</code> table: </p><div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:php;toolbar:false;'>SELECT customer_id, name FROM customers;</pre><div class="contentsignin">Copy after login</div></div><p><strong>WHERE clause</strong></p><p><code>The WHERE</code> clause is used to filter the retrieved data and return only rows that meet certain criteria. Conditions can use comparison operators (such as <code>=</code>, <code>></code>, <code><</code>), logical operators (such as <code>AND</code>, <code>OR</code>) and wildcard characters (such as <code>%</code>, <code>_</code>). </p><p><strong>Example</strong></p><p>The following query retrieves all orders with a total order price greater than $100 from the <code>orders</code> table: </p><div class="code" style="position:relative; padding:0px; margin:0px;"><pre class='brush:php;toolbar:false;'>SELECT * FROM orders WHERE total_price > 100;</pre><div class="contentsignin">Copy after login</div></div><p><strong>Other data retrieval commands</strong></p> <p>In addition to the <code>SELECT</code> command, SQL also provides other commands for data retrieval, including: </p> <ul> <li> <code>DISTINCT</code>: Return a unique value </li> <li> <code>GROUP BY</code>: Group the data by the specified column </li> <li> <code>HAVING</code>: Apply to the grouped data Filter condition</li> <li> <code>ORDER BY</code>: Sort data by specified column</li> </ul>

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