To eliminate duplicate values, use the DISTINCT clause. In MySQL, you can get the concatenated values of expression combinations Then the string combining operation will be performed.SELECT id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id The reason for this sign is that if we use any non-character parameters in the CONCAT function, these parameters will be converted into the string data type automatically by SQL Server. Tip: CONCAT function in SQL performs implicit conversion if any non-string data type parameter passes.Īs we mentioned above, there is a warning sign shown on the SELECT operator in the execution plan. In the following tip, we will highlight another issue about the execution plan that is CONVERT_IMPLICIT operation. With this example, we demonstrated that the data conversion operation is made by the CONCAT function. Particularly for this query, the integer (INT) data type expressions are converted to strings (VARCHAR). Now, we will click the Operations tab to find out more details about the Compute Scalar operator.Īs we can clearly see, a data conversion occurred while the query was executing. We will mention the details of this warning sign in the following tip. A warning sign shows on the SELECT operator. In the final step of the execution plan, the SELECT operator represents the result of the query. Compute Scalar operator performs a scalar computation and takes the task of completing the CONCAT function operation for this query execution. On the other hand, if we find out this operator for any table which has a huge number of rows, this situation may indicate a performance issue. However, this isn’t a problem for this table because it contains only one row. The table scan operator indicates that the query optimizer is required to read whole data of the Test_NumericValue because it does not contain any index. Let us briefly explain the query plan mentioned above. The reason why we analyze the execution plan is that all details about the query processing operation are hidden in it: In this step, we will analyze the actual execution plan details of the query. SELECT CONCAT ( Number_1, Number_2, Number_3 ) FROM Test_NumericValue In this example, we will join Think and green strings with the CONCAT function: The CONCAT function at least requires two parameters and this function can accept a maximum of 254 parameters. The syntax of the function looks like as follows:ĬONCAT ( string_value1, string_value2 ) Now, we will go into the point with a simple example.
CONCAT function is a SQL string function that provides to concatenate two or more than two character expressions into a single string. CONCAT function in SQL is one of the most useful members of these functions. SQL string functions are used to manipulate the character expressions or to obtain various information about them. We can use nvarchar(max) or varchar(max) instead. These data types are deprecated, and for this reason, we should try not to use these data types. We have to take into account one point about the text and ntext data types. Unicode character strings data types that store Unicode character data These are:Ĭharacter strings data types that store non-Unicode character data In terms of SQL Server, we can categorize SQL string data types into different two groups. In this article, we will explore the syntax, working mechanism and other details of the CONCAT function in SQL and we will also make up various different examples about it.Ī string is a set of characters that helps to declare the texts in the programming languages.
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