sql query with nolock

SQL query begins with a specified character SQL query statementLike a lot of time we need to be in the MySQL tutorial, MSSQL to query eligible data, today I came across a query with "Deng" all the conditions of the beginning of th

[Name],subject,score Here for a good understanding only one column to get the following results With the example of the language accomplishment line train, it is easy to add the other two columns, Select [Name],Chinese =caseWhen subject= ' language ' then score else 0EndMathematics =caseWhen subject= ' math ' then score else 0EndForeign Language =caseWhen subject= ' foreign language ' then score else 0EndFrom StudentscoreGroup BY [Name],subject,score The following is the result of the

scroll lock depends on the cursor concurrency option and the lock prompt in the SELECT statement of the cursor. Optimistic read-only value * Specifying the nolock prompt will make the table with the specified prompt read-only in the cursor. 16. Use profiler to track the query, obtain the time required for the query, and locate the

When converting Oracle queries to SQL queries, you need to pay attention to a lot of issues. The following gives you a detailed analysis of the number trade-offs in converting Oracle queries to SQL queries for your reference. Number trade-offs Oracle Database has a TRUNC function, which returns n digits of the m-bit decimal number. If m is omitted, n is 0 digits. The m value can be negative, indicating th

cursor concurrency option and the lock prompt in the SELECT statement of the cursor. Optimistic read-only value * Specifying the nolock prompt will make the table with the specified prompt read-only in the cursor. 16. Use profiler to track the query, obtain the time required for the query, and locate the SQL probl

=name; This. Minage =Minage; This. MaxAge =MaxAge; } PublicString GetName () {returnname; } Public voidsetName (String name) { This. Name =name; } Public intGetminage () {returnMinage; } Public voidSetminage (intminage) { This. Minage =Minage; } Public intGetmaxage () {returnMaxAge; } Public voidSetmaxage (intMaxAge) { This. MaxAge =MaxAge; } }configuration file for 4.sql queries Selectusermapper.xmlnamesp

When we query information in the database, we often need to query the information based on the conditions entered by the user. Some conditions are available, but some conditions are unavailable. Therefore, we need to assemble the condition statements. The following method is compiled based on this situation, hoping to help the reader: String SQL = "select * fr

(SelectMAXfromorderbydesc; Meaning: First check out the tallest height, exclude the height, then sort the data (descending) and query out the current first piece of data. 2, the query may be the same as the highest height value of the second place, that is, if the height is 182 Several people are also 182 height, The second place is still Select Top 1 * from (selecttop2fromorderbydescOrder by

Query, delete, insert, query, sort SQL statementHere we provide query, delete, insert, query, sort totals sum average max minimum SQL statement OH.Selection: SELECT * FROM table1 whereInserting: INSERT INTO table1 (field1,field2)

Label:In SQL Server, each query will find the shortest path to achieve its own goal. If the database accepts only one connection at a time, only one query is executed. Then the query is, of course, M.F.B. s to complete the work. For most databases, however, multiple queries need to be processed at the same time. Instea

SQL statement Optimization-query different rows of the two tables NOT IN, NOT EXISTS, Join query Left Join, existsleft In actual development, we often need to compare the differences between two or more tables and compare the data that is the same and the data is different. At this time, we can use the following three methods: 1. IN or not in, 2. EXIST or NOTEXIS