Truy vấn trong PHP
Giá trị trả về. Đối với CHỌN, HIỂN THỊ, MÔ TẢ hoặc GIẢI THÍCH, nó trả về một đối tượng mysqli_result. Đối với các truy vấn thành công khác, nó trả về true. Mặt khác, nó trả về false khi thất bại Show Hãy hiểu cách chúng ta có thể thực thi một truy vấn SQL Thực hiện một truy vấn SQL. Chúng tôi sẽ hiểu cách chúng tôi có thể thực hiện một truy vấn SQL với một ví dụ. Chúng tôi sẽ tạo một cơ sở dữ liệu, bảng và sau đó chèn một số giá trị vào đó Ví dụ. Tạo cơ sở dữ liệu và chèn một số giá trị vào đó PHPTable has been created successfully71 Table has been created successfully72 Table has been created successfully73 Table has been created successfully74 Table has been created successfully75 Table has been created successfully76 Table has been created successfully72 Table has been created successfully1 Table has been created successfully74 Table has been created successfully3 Table has been created successfully76 Table has been created successfully72 Table has been created successfully6 Table has been created successfully74 Table has been created successfully8 Table has been created successfully76 New record created successfully0 Table has been created successfully72 New record created successfully2 Table has been created successfully74 New record created successfully4 New record created successfully5 Table has been created successfully73 New record created successfully7 Table has been created successfully1 New record created 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successfully7 Table has been created successfully6 New record created successfully7 Table has been created successfully766 Table has been created successfully21 Table has been created successfully14 Table has been created successfully23 Table has been created successfully24 New record created successfully2 Table has been created successfully26 Table has been created successfully19 Table has been created successfully28 Table has been created successfully24 Table has been created successfully710 Table has been created successfully711 New record created successfully2 Table has been created successfully713 Table has been created successfully14 Table has been created successfully715 New record created successfully0 Table has been created successfully72 Table has been created successfully718 Table has been created successfully31 Table has been created successfully14 Table has been created successfully33 Table has been created successfully14 Table has been created successfully35 Table has 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created successfully715 New record created successfully0 Table has been created successfully72 New record created successfully2 Table has been created successfully747 Table has been created successfully748 đầu ra Table has been created successfully Chèn một số giá trị vào bảng “Emp” PHPTable has been created successfully71 Table has been created successfully72 Table has been created successfully73 Table has been created successfully74 Table has been created successfully75 Table has been created successfully76 Table has been created successfully72 Table has been created successfully1 Table has been created successfully74 Table has been created successfully3 Table has been created successfully76 Table has been created successfully72 Table has been created successfully6 Table has been created successfully74 Table has been created successfully8 Table has been created successfully76 Table has been created successfully72 Table has been created successfully766 Table has been created 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has been created successfully713 Table has been created successfully72 Table has been created successfully715 Table has been created successfully72 Table has been created successfully718 New record created successfully20 _______421____422____423____47 New record created successfully25 New record created successfully26 New record created successfully0 Table has been created successfully72 Table has been created successfully23 Table has been created successfully24 New record created successfully2 Table has been created successfully726 Table has been created successfully718 Table has been created successfully728 Table has been created successfully27 Table has been created successfully730 New record created successfully37 Table has been created successfully76 Table has been created successfully72 Table has been created successfully715 Table has been created successfully735 Table has been created successfully736 Table has been created successfully27 Table has been created successfully730 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Vì chúng tôi đã sử dụng AUTO_INCREMENT, nên nó sẽ tự động chèn bản ghi có “id=1” và với mỗi bản ghi mới được chèn, nó sẽ tăng “id” lên một Lấy kết quả từ cơ sở dữ liệu PHPTable has been created successfully71 Table has been created successfully72 Table has been created successfully73 Table has been created successfully74 Table has been created successfully75 Table has been created successfully76 Table has been created successfully72 Table has been created successfully1 Table has been created successfully74 Table has been created successfully3 Table has been created successfully76 Table has been created successfully72 Table has been created successfully6 Table has been created successfully74 Table has been created successfully8 Table has been created successfully76 Table has been created successfully72 Table has been created successfully766 Table has been created successfully74 Table has been created successfully768 Table has been created successfully76 New record created successfully0 Table has been created successfully72 New record created successfully2 Table has been created successfully74 New record created successfully4 New record created successfully5 Table has been created successfully73 New record created successfully7 Table has been created successfully1 New record created successfully7 Table has been created successfully6 New record created successfully7 Table has been created successfully766 Table has been created successfully21 Table has been created successfully72 Table has been created successfully23 Table has been created successfully24 New record created successfully2 Table has been created successfully26 Table has been created successfully27 Table has been created successfully28 Table has been created successfully24 Table has been created successfully710 Table has been created successfully711 New record created successfully2 Table has been created successfully713 Table has been created successfully72 Table has been created successfully715 New record created successfully0 Table has been created successfully72 Table has been created successfully718 Table has been created successfully74 Table has been created successfully212 Table has been created successfully76 Table has been created successfully72 Table has been created successfully215 Table has been created successfully74____42 Table has been created successfully726 Table has been created successfully718 Table has been created successfully21 Table has been created successfully72 Table has been created successfully23 Table has been created successfully24 Table has been created successfully215 Table has been created successfully225 Table has been created successfully27 Table has been created successfully227 Table has been created successfully24 Table has been created successfully229 Table has been created successfully74 Table has been created successfully215 Table has been created successfully232 New record created successfully21 Table has been created successfully730 Table has been created successfully235 Table has been created successfully711 Table has been created successfully229 Table has been created successfully238 Table has been created successfully239 Table has been created successfully240 Table has been created successfully241 Table has been created successfully242 Table has been created successfully711 Table has been created successfully229 Table has been created successfully238 Table has been created successfully246______1240 Table has been created successfully248 Table has been created successfully711 Table has been created successfully229 Table has been created successfully238 Table has been created successfully252 Table has been created successfully240 New record created successfully49 Table has been created successfully76 PHP có phải là ngôn ngữ truy vấn không?PHP là ngôn ngữ kịch bản phổ biến nhất để phát triển web . Nó miễn phí, mã nguồn mở và phía máy chủ (mã được thực thi trên máy chủ). MySQL là Hệ thống quản lý cơ sở dữ liệu quan hệ (RDBMS) sử dụng Ngôn ngữ truy vấn có cấu trúc (SQL). Nó cũng miễn phí và mã nguồn mở.
Làm cách nào để thực hiện truy vấn trong PHP?Chúng ta có thể thực hiện truy vấn đối với cơ sở dữ liệu bằng cách sử dụng phương thức mysqli_query() của PHP . cú pháp. Chúng ta có thể sử dụng phương thức mysqli_query() theo hai cách. Phong cách hướng đối tượng. phong cách thủ tục.
Truy vấn trong cơ sở dữ liệu là gì?Truy vấn có thể là yêu cầu kết quả dữ liệu từ cơ sở dữ liệu của bạn hoặc hành động đối với dữ liệu hoặc cho cả hai . Một truy vấn có thể cung cấp cho bạn câu trả lời cho một câu hỏi đơn giản, thực hiện các phép tính, kết hợp dữ liệu từ các bảng khác nhau, thêm, thay đổi hoặc xóa dữ liệu khỏi cơ sở dữ liệu.
Việc sử dụng truy vấn chọn trong PHP là gì?Có thể sử dụng truy vấn select trong từ khóa PHP làm tiền tố để chọn các bản ghi từ một bảng . Truy vấn chọn trả về một tập hợp các bản ghi từ một hoặc nhiều bảng được chỉ định. CHỌN là một lệnh có thể được sử dụng để chọn một bản ghi từ một bảng. Các cột của bảng Tên bảng của tôi là cột A>, cột B>, v.v. |