toad sql query

+ @WHERE -- ----Execution statistics EXEC sp_executesql @COUNTSQL, N ' @RECORDCOUNT INT out ', @RECORDCOUNT out -- ----Count pages SET @PageCount = CEILING (@RecordCount * 1.0/@PageSize) -- ----Query statement DECLARE @SQL NVARCHAR (2000) DECLARE @ORDERBY VARCHAR (100) SELECT @ORDERBY = ' ORDER by Tbsdinfo. Iscommon desc,tbsdinfo.commontime Desc,tbsdinfo. Createtime DESC ' IF (@PAGEINDEX =1

Article 1: how to optimize slow query SQL statements in MySQL56-Introduction to slow logs: in actual log analysis, there are usually a large number of slow logs, at the same time, there will be a large number of records for the same query. here we need to find the most problematic and optimized log in the actual log analysis, generally, the number of slow logs is

server| Speed | optimization MS SQL Server Query optimization method (1) There are many reasons for the slow query speed, common as follows: 1, no index or no index (this is the most common problem of query slow, is the defect of program design)2, I/O throughput is small, creating a bottleneck effect.3. No computed col

SELECT type,--clerk type sum (virtual_memory_reserved_kb) as vm_reserved_kb,--reserved Memory sum (VIRTUAL_MEMORY_COMMITTED_KB) as VM_COMMITTED_KB,--committed memory sum (awe_allocated_kb) as awe_allocated_kb,--the memory sum (shared_memory_reserved_kb) as SM used when opening awe _RESERVED_KB,--shared reserved memory sum (shared_memory_committed_kb) as sm_committed_kb,--shared commit memory sum (single_pages_kb) as SINLGEPAGE_KB,--Buffer pool stolen Memory sum (multi_pages_kb) as multipage_kb--

First of all, let's look at one of the steps here that translates into banner, which requires pivot, step-by-step Then look at the overall query results for the two query methods after the main table join So take a look at the latter query method is also through the industry after the conversion to do the join execution plan, you can see only the Word table

Recursive queries using CTE (common table expressions) ---- SQL Server 2005 and later versions A common table expression (CTE) has an important advantage: It can reference itself to create a recursive CTE. Recursive CTE is a public table expression that repeats the initial CTE to return a subset of data until the complete result set is obtained. When a query references recursive CTE, it is called recursive

Hibernate native SQL query Multiple table Association, SQL statement to pay attention to the problem@for ever 2009-9-4System environment:MySQL5.1Hibernate3.3The assumption is as follows:The entity classes Question and answer correspond to the data table Question and answer respectively.and the fields of table question and answer are mostly the same, and the numbe

Grouping query of SQL is very useful, but sometimes its features are also annoying. Take a good look at this SQL: select employer_name, department, max(salary) from employer_salary group by department; Query the name and salary number of the highest-paying person in each department. Is there a problem with this

One: LINQ is not a unique query for EF ...Two: Entity Sql1. ESQL = Entity SQL ... "Class SQL language" is about the same as SQL, but not SQL ...using (schooldbentities db = new Schooldbentities ()){Querying with Object Services and Entity SQLString sqlString = "Select Value

Pq_distribute hints are often used to improve the performance of connection operations between partitioned tables in the Data Warehouse. The Pq_distribute hint allows you to determine how table data rows participating in a connection are allocated between production and consumption parallel query service processes. Pq_distribute prompt accepts three parameters: table name, outer allocation, and internal allocation.When parallel

Now the development system involves querying by page. when doing this, I am thinking, whether or not the query SQL statement can be automatically encapsulated by parameters into the ability to count the data size of the query statement that is not queried by page. for example, the general practice is: 1. first query ba

expected results, change the query conditions, the sorting result becomes unrecognizable (the impact of the execution plan change).In a nutshell: No sorting is performed explicitly, and it is not expected that the query results will be sorted every time, even every time. Summarize: This article is based on two simple examples,From two aspects of execution planning and physical storage, "If

Analysis of SQL Server's focus on using indexes and query execution plans and SQL Execution plans Preface In the previous article "Analysis of the Impact of SQL Server focused indexes on non-clustered indexes", we talked about the impact of clustered indexes on non-clustered indexes and the performance optimization tha

The more CPU and IO resources a query requires, the slower the query speed. Therefore, another way to describe the query performance tuning task is, the query command should be rewritten in a way that uses less CPU and IO resources. If the query can be completed in this way,

The SELECT clause is logically the last step in the final processing of the SQL statement, so the following query will have an error: SELECT year (OrderDate asorderyearCOUNT(DISTINCT CustomerID fromdboGROUP by OrderYear; Because group by was preceded by a SELECT, the OrderYear column was not formed at that time. If you want to query for su

the same, then the greater than and equals sign are the same)1.select gid,fariqi,neibuyonghu,reader,title from Tgongwen where fariqi> ' 2004-1-1 ' and fariqiSpents: 3280 milliseconds4. The date column will not slow down the query speed because there is a minute or seconds inputIn the following example, there are 1 million data, 500,000 data after January 1, 2004, but only two different dates, the date is accurate to the day, before the data 500,000,

Theoretical background1. sql:structured Query Language is the standard language for querying and managing data for RDBMS (relational Database Management Systems).2. Understanding set theory and predicate logic, RDBMS is based on these two mathematical branches.3. SQL statement Category:Data definition Language, DDL: The definition language, which handles the definition of objects, including statements such

In the process of paging data using temporary tables, it is found that the query statement conditions are passed through the stored procedure parameters. The parameter conditions cannot be directly used after the SQL where statements are added. There is only one solution to this problem, it is to concatenate SQL statements and conditions into an

1. SQL statements Is a language Meets ANSI standards Keyword cannot be abbreviated Use statements to control the definition information and data of tables in the database SQL is the abbreviation of Structured Query Language (Structured Query Language. You can use SQL statem

Original: SQL query performance analysisOriginal source: http://blog.csdn.net/dba_huangzj/article/details/7623926The performance of SQL query directly affects the value of the whole database, which must be treated solemnly.SQL Server provides a variety of tools, and here's a simple introduction:First, the