scalar value

First, ExecuteNonQuery and ExecuteScalarUpdates to the data do not need to return a result set, and ExecuteNonQuery is recommended. The network data transfer is omitted because no result set is returned. It simply returns the number of rows affected.

Create a Connection object first$connection = new \yii\db\connection ([ ' dsn ' = = $dsn, ' username ' = = $username, ' password ' = ' $ ' Password,]); $connection->open ();The query returns multiple lines: $command =

1.Using SQLQueryThe control of native SQL query execution is performed through the SQLQuery interface, by executing the session. Createsqlquery () Gets the interface. In the simplest case, we can take the following form:List cats =

Stored procedures:Stored procedures can make it much easier to manage the database and to display information about the database and its users. A stored procedure is a precompiled collection of SQL statements and optional control-flow statements,

1. Use anti-quotation marks to call an external program and return the output of the program, such as $cwd = ' pwd ';2. The difference between the variable types in Perl is mainly singular and plural;   Singular variables are called scalar $scalar,

String is a collection of character (character)-type values such as "Hello, World", "Thief King", represented by a string type.Swift's string and character types provide a fast, Unicode-compatible way to handle textual information in code. The

Apply function (evaluates an array by row or column): Use the format as:Apply (X, MARGIN, fun, ...) where x is an array, the margin is a vector (indicating whether to apply the function fun to the row or column of x), or 1 for the row, 2 for

Yii2 database read/write splitting configuration example, yii2 example To start using a database, you must first configure the database connection component and add the db component to the application configuration. (the "Basic" Web application is

Yii2 -- Use Database Operation Summary (add, delete, query, modify, and transaction), and add and delete yii2 This article introduces Yii2-Database Operation Summary (add, delete, query, modify, and transaction), as follows: Object operations Query /

PHP 2D array assignment details. PHP has many things worth learning. here we mainly introduce the assignment of two-dimensional arrays in PHP. let's briefly summarize PHP. For general computer enthusiasts, PHP may be a PHP with many things worth

Amp; lt; amp; gt; operatorinMySQL Opera Have you ever seen "" in a SQL query while using MySQL? Does it mean less and equals to and greater? Actually if you consider it as the union of , great, you are close to it. this is one form of equal

This time for you to bring the Python interface using the OpenCV method, Python interface using the OpenCV of attention to what, the following is the actual case, together to see. First, in the ANACONDA2 configuration OpenCV Unzip OPENCV, add

Basic knowledge of C # IXWritten by Zhu Zhu, please specify from Zhu Zhu Homeland http://blog.csdn.net/zhgl76881. LINQ queries use: Query syntax and method syntax. The former is a declaration form similar to the SQL statement, written in the form of

Continue the previous article ASP. NET development, from the second layer to the third layer, to the object-oriented http://www.cnblogs.com/insus/p/3822624.html. We learned how to change our program from Layer 2 to Layer 3. In this article, we will

LEAD and LAG functions in SQL SERVER LEAD and LAG Functions LEAD Access Data in subsequent rows of the same result set, instead of using the self-join in SQL Server 2012. LEAD provides row access based on the given physical offset after the current

Learning notes TF019: sequence classification, IMDB rating classification, tf019imdb Sequence classification: used to predict the category tags of the entire input sequence. Sentiment analysis predicts users' attitudes towards writing text topics.

When we write the traversal array, there are several methods, such as $ arr [\ 'key \ '], $ arr [\ "key \"], and $ arr [key ]. outgoing content, but where are their differences? Let me introduce them below. I. Differences between $ arr ['key'] and $

RxJava development essentials 2-why is it Observables?Why is it Observables? In the object-oriented architecture, developers are committed to creating a group of decoupled entities. In this way, entities can be tested, reused, and maintained without

SQL function description: Once data is successfully retrieved from a table, you need to further manipulate the data to obtain useful or meaningful results. These requirements include execution of computation and mathematical operations, conversion

ASP. NET Web Pages-Database object, pagesdatabaseASP. NET Database object reference manual Close () Close the opened database. Dispose () Releases all resources used by the Database instance. Database. Execute