sql query book

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SQL statement used to query the TABLE quantity and name of a database in SQL Server

In SQL ServerEach database has a table generated by the system.The table sysobjects records all the table names in the database.We can use the following SQL syntax for query operations. Copy codeThe Code is as follows:Select Name, id from sysobjects where xtype = 'U' Xtype = 'U' indicates the table used. If xtype = 's' is used'The default table There is also a

SQL query statements for this year, month, and today, with SQL date functions _mssql

Check this diary record SELECT * FROM Messages WHERE convert (Nvarchar, createdate, MR) = CONVERT (Nvarchar, GETDATE (),) Order by CreateD Ate DESC SELECT * from table WHERE DateDiff (day, column name , GETDATE ()) =0 Check this year SELECT Count (*) from Messages WHERE DateDiff (year,createdate,getdate ()) =0 Query this month SELECT Count (*) from Messages WHERE DateDiff (month,createdate,getdate ()) =0 This week 's record SELECT * from

SQL BASE Statement-sql query statement Select

a joins Dept b on (a.deptno = B.deptno) Order BY empno Desc;To sort by an alias of a field or an expressionSelect A.ename,a.mgr,a.empno, (a.sal*12) as annsal from EMP a order by annsal;1.5 GroupingSelect B.deptno,b.dname,sum (a.sal)From EMP a,dept bwhere A.deptno=b.deptnoGROUP BY B.deptno,b.dnameORDER BY B.deptno DescFields after GROUP by = ALL display fields except aggregate functions in the select listThe total wage, the number of people, the maximum wage, the minimum wage, the average wage o

Aliases in Ssm-mybatis-05:mybatis, SQL fragment and fuzzy query plus Getmapper

------------I do not have him, but the hand is ripe, humble and foolish, and eager to be hungry-------------A brief overview of this lectureAlias, SQL Snippet write a little bit more, fuzzy query write moreOne. Alias  "Cn.dawn.demo01.entity.Book " alias="book">"cn.dawn.demo01.entity">  Aliases are written in large configurationsTwo.

Use of SQL tuning (SQL TUNING) parallel query hint (Hints) pq_distribute

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

SQL-difference and performance of SQL statements that query statistical data volume when MySql executes paging

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

To get the metadata for the SQL query result set column based on the SQL query

Label:ioarjavaforsp Data onbsad Publiclist To get the metadata for the SQL query result set column based on the SQL query

The SQL statement is used to query the Index usage and the index status of the SQL statement.

The SQL statement is used to query the Index usage and the index status of the SQL statement. SELECT sch.name + '.' + t.name AS [Table Name], i.name AS[Index Name], i.type_desc, ISNULL(user_updates,0) AS [Total Writes], ISNULL(user_seeks +user_scans + user_lookups,0) AS [Total Reads], s.last_user_seek, s.last_user_scan , s.last_user_lookup, ISN

Use SQL statements in SQL Server to query the names of stored procedures referenced by all other stored procedures.

This issue is especially important for projects with a relatively large scale. If there are hundreds of stored procedures in the database,I can't find them one by one. Even if I understand the business and system very well, it will take a long time to remember.How can I use SQL statements for queries?The following describes how to query SQL statements:Copy codeTh

[SQL] T-SQL recursive query (a method for a given node to check all parent nodes, all child nodes)

--Find all parent nodesWith TAB as(Select Type_id,parentid,type_name from sys_paramtype_v2_0 where type_id=316--child nodesUNION ALLSelect B.type_id,b.parentid,b.type_nameFromtab a,--child node datasetsSys_paramtype_v2_0 B--parent node data setWhere a.parentid=b.type_id--the child node DataSet. Parendid= The parent node data set. Id)SELECT * from tab;--Find all child nodesWith TAB as(Select Type_id,parentid,type_name from sys_paramtype_v2_0 where type_id=1--parent nodeUNION ALLSelect B.type_id,b

How SQL Server saves the contents of a query to a new SQL table

Tags: style time span stat name not sel tab DUPI'm using a statement to save the queried data to a new table 1) using the into table statement, the new table that needs to be saved does not need to be created in advance Select * to from table-Insert new Table statement into TableName 2) using the Insert Table statement, the new table that needs to be saved does not need to be created in advance CREATE TABLE [dbo].[newtable]( [Fdsequenceid][bigint] not NULL, [Fdinnertime][Da

Analysis of SQL Server's focus on using indexes and query execution plans and SQL Execution plans

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

SQL Server T-SQL Query Learning Notes (1) _mssql2005

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

SQL Server-T-code Basic Tutorial--t-sql query and programming background

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

Multi-condition query without concatenating SQL strings during SQL server storage

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

SQL statement implementation query SQL Server memory usage _mssql

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--

MySQL database using SQL command Window query data, changed to SQL statement imported into MySQL database

1. The query statement is select * from t_table; The exported data format is as follows:2. Back up the data text, then open it using notepad++, then copy the data to the new TXT and replace it as follows:1) will "| "Delimiter (delimiter of different fields), replace with ', ' is the delimiter of the different fields in the SQL statement;2) Leave the leftmost "|" For each row of data "Replace with (') the le

Use ms SQL to implement distributed query of heterogeneous databases using t-SQL code (original)

/* Use ms SQL to implement the T-SQL code for Distributed Query of heterogeneous databases */ Exec sp_addrole server 'Ms _ SQL ', '', 'sqloledb', '2017. 18.9.20'Exec sp_add1_srvlogin 'Ms _ SQL ', 'false', null, 'sa', 'capec '/* Create a sqlserver remote connection to the sq

Use SQL statements to query all commands being executed in SQL

If your experience in SQL is not rich enough and you have not solved many problems in SQL, read this chapter carefully, it helps you avoid a mistake that is likely to be made frequently! Create a test table first. Create Table # Table1 (ID int identity (1, 1) primary key, col1 int not null, col2 decimal (18, 1 )) Insert data Insert into # Table1 (col1, col2) Select 0, 0.1 Union all select 1, 1.1 Uni

Under SQL SERVER: 1, recursively query the sub-categories under the parent classification. 2. Check the top two items in each product category SQL

Tags: open window function query desc font where SRC definition nio return1. Recursively query the sub-categories under the parent classification. Table Design: Sql: --CTE Statement (for later versions of MSSQL2005) withCte_testnavi (id,name,pid) as ( --This is the query statement SELECTId,name,pid fromNaviWHEREName=

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