sql all in one for dummies

The field stores the timestamp. how to obtain all records of the day? how to write SQL statements? solution ------------------ SQLcodeSELECT * fromtablewhereDATE (FROM_UNIXTIME (time )) DATE (NOW (); ------ solution ---------------- The Field stores the timestamp. The field stores the timestamp. how does one obtain all records of the current day? How does one wr

null-null NULL int int North Wind TRADE dbo departmentsalaryinfo;1 @department 1 1 0 NULL 1 129 null NULL varchar var Char North Wind trade dbo departmentsalaryinfo;1 @average 2 2 0 NULL 1 6 NULL null-NULL NULL Money Money North Wind trade dbo departmentsalaryinfo;1 @maximum 3 2 0 NULL 1 6 NULL null-NULL NULL Money Money North Wind trade dbo departmentsalaryinfo;1 @minimum 4 2 0 NULL 1 6 NULL null-NULL NULL Money Money --Parameter name, argument type, parameter length in stored procedure Sele

The original Article is from the previous article on the Internet, but there are some problems with the original storage process. This article has been verified and further corrected, and the backup date is automatically added when backup is added. The content of this article is as follows: Stored Procedure of backup Processing Set ansi_nulls onSet quoted_identifier onGo /* -- Back up all databasesThe backup file name is database name + date +. BakSet

DDL cannot be rolled back because the DDL is not transactional.To implement automatic rollback. (Begin,commit,rollback), only DML is included in the SQL statement.In this way, automated publishing is restricted to the canonical format.Therefore, one-size-fits-all approach is to assume that all SQL does not support tran

Original: The simplest way to delete all data in SQL ServerThe simplest Way to delete all data in SQL Server Author : CC Abba 2014-3-14 in fact, the method of deleting the data in the database is not complicated, why do I have to superfluous it, one is that I am here to delete

I. BACKGROUND In the performance tuning or need to understand a database table information, the most intuitive way is to list the data of all the table information, including: The number of records of the table, data capture space, index footprint, unused space, etc. (as shown in Figure1), With this information you can simply determine that the pressure on the database from the data may be caused by a certain table. Because the larger the table data,

Expert answers By querying three system tables in any database, you can obtain the default values of each field in each table. The following is the core query. It returns the default value allocated to each user table in the current database. This query is compatible with SQL 2000 and SQL 2005. Quote: CopyCode The Code is as follows: Select so. Name as "table name", SC. Name as "column name", Sm. Text as

Expert answersBy querying three system tables in any database, you can obtain the default values of each field in each table. The following is the core query. It returns the default value allocated to each user table in the current database. This query is compatible with SQL 2000 and SQL 2005.　　 Quote:Copy codeThe Code is as follows:Select so. name as "Table Name", SC. NAME AS "Column Name", SM. TEXT AS "De

Method 1:When the publisher filter condition is NULL, how do you write SQL?1 DECLARE @publishers VARCHAR (50);2 SELECT * FROM dbo. Book WHERE Publishers=isnull (@publishers, publishers)Method 2:DECLARE @cinv varchar (50)SELECT * from inventory where 1=1 and ([email protected] or @cinv is null)Method 3:DECLARE @name VARCHAR (+), @page INT =1SET @name = ' Zhang San 'DECLARE @sql VARCHAR (1000)SET @

SQL out all Saturday Sunday dateCREATE TABLE Satsun ([id] int identity (), [Date] datetime,[weekday] char (6))GoDECLARE @datetime datetime, @weekday char (6)Set @datetime = ' 2007-1-1 'While @datetime BeginSelect @weekday =datename (Weekday, @datetime)If @weekday = ' Saturday ' Insert Satsun ([Date],[weekday]) VALUES (@datetime, @weekday)If @weekday = ' Sunday ' Insert Satsun ([Date],[weekday]) VALUES (@dat

UNION ALL the purpose of this instruction is to merge the results of two SQL statements together. The union all and the Union differ in that the Union all lists each qualifying data, regardless of whether the data value is duplicated or not. The syntax for union ALL is as f

SQL FOR XML alternative notation (with tag and union all, simple and easy to understand)Test environment: SQL, R2, 2010, 2012, 2014, etc.Declare @agent table (agentid int, Fname varchar (5), SSN varchar (one)) insert into @agent Select 1, ' Vimal ', ' 123-23-4521 ' UNION ALL Select 2, ' Jacob ', ' 321-52-4562 ' union

The purpose of this example is to: 1 Learn how to traverse all files in a specified folder 2 how the console enters and outputs the data code:Using system;using system.io;namespace tosql{class tosql{static void Main () {String path = System.Environment.CurrentDirectory; System.Console.WriteLine ("Enter the folder name to read"); string name = Console.ReadLine ();p ath + = "\" + name; Getallfile (path);} public static void Getallfile (string path) {Dir