10 article Recommendations for conditional queries

This article mainly introduces the MVC cross-database Multi-table federated dynamic Condition query function, which is based on the example form, and analyzes the implementation technique of ASP. A friend you need can refer to the example of this article describes the MVC cross-database Multi-table federated dynamic Condition query function implemented by ASP. Share to everyone for reference, as follows: First, the Controller method [Httpget]public ActionResult Search () {viewbag.headtitle = "search"; Viewbag.metakey = "\" 123\ ""; Viewbag.metades = "\" 456\&qu

1. code example of an ASP. NET cross-database multi-table federated dynamic Condition query

Introduction: This article mainly introduces the MVC cross-database Multi-table federated dynamic Condition query function, combined with the instance form, it analyzes the implementation technique of the multi-database multiple-table joint query based on MVC architecture in detail.

2. mysql Common basic operational Syntax (vi)--conditional query on data ordering and limiting the number of results "command line mode"

Summary: 1. Use order by to sort the results of the query, ASC ascending, desc descending: You can also specify multiple field names and sort orders by the order by: 2, limit the number of query results by using limit: 0, which represents the starting position of the query, It can also be understood as the number of skipped, and 2 in the number of queries required. There are 3 data in this table because the number of bars is limited to 2, so the actual result is only two. In addition, the initial position here is 0, actually can not write, the default is 0: Here is another situation, is

3. mysql Common basic operation Syntax (v)--Simple conditional query on data "command line mode"

Introduction: 1, single-Condition query: Select field name from TableName where condition; 2, simple multi-condition query, using && or between and etc: 3, is null and are NOT NULL query, It is important to note that NULL is not an empty string, not a 0:4, in, and not in query, which is equivalent to connecting the set element behind in with OR. Note that if NULL is present in the collection behind the in band, the result is not affected, but there is no in the back of the collection with NULL, it does not

4. mysql Common basic operation Syntax (iv)--simple unconditional query on data and library and table query "command line mode"

Introduction: 1, MySQL simple query: Select field 1, Field 2 ... from tablename; if the field writes A *, which represents all the fields in the query, it is equivalent to specifying all the field names, so if you want to query data for all fields, it is generally used *. 2, go to re-query: SELECT DISTINCT field 1, Field 2 ... form tablename; can be compared with the results of the previous picture. 3, directly in the query to do math arithmetic, subtraction: 4, query results to query the word

5. PHP Query and multi-conditional query

Introduction: This article to you to share is the use of PHP to implement single conditions and multi-conditional query code and examples, very practical, the need for small partners can refer to the following

6. MySQL Advanced (v) multi-criteria query with or in the datasheet

Summary: The OR keyword can be queried by combining multiple criteria. When using the OR keyword:

7. PHP processing of HTML-encoded strings

Introduction: Today, when writing a PHP script to access the database, it was found that the Chinese characters are stored in HTML encoding (such as "Mao" in the text of the HTML code "& #27611;") ), which makes it impossible to query in Chinese when a conditional query is made on the field, and to convert it to encode before conditional matching. The htmlentities and Html_entity_decode functions are required in PHP to convert the readability character to the HTML encoded character. Then write the following query statement, ...

8. How to implement data query data from the time to judge if the data is more than N sub-query recursive?

Introduction: For example, the database has 300,000 data now according to the criteria of the query to meet the 30,000 data to take too much time may be slow or other problems I would like to take 100,003 times to take out this is just an example of how to achieve AH? With recursion? Thanks for the notice!!! And if you look at the number of two tables ...

9. PHP processing of HTML-encoded strings

Introduction: Today, when writing a PHP script to access the database, it was found that the Chinese characters are stored in HTML encoding (such as "Mao" in the text of the HTML code "& #27611;") ), which makes it impossible to query in Chinese when a conditional query is made on the field, and to convert it to encode before conditional matching. The htmlentities and Html_entity_decode functions are required in PHP to convert the readability character to the HTML encoded character. Then write the following query statement, ...

SQL multi-Conditional query

Introduction: To implement a multi-conditional query where the value of 0 is an unlimited number of conditions How to use SQL implementation for example: Query a certain type of shop in the region may be open to any type of Chinese food query when you do not need the where region = value, but only where type = Chinese, select the region for Beijing type for Chinese food query when ...

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