sql all in one for dummies

.[value], ") as [description]From Syscolumns ALeft join Systypes B on A.xtype=b.xusertypeINNER JOIN sysobjects D on a.id=d.id and d.xtype= ' U ' and d.nameLeft join syscomments E on a.cdefault=e.idLeft joins Sys.extended_properties G on a.id=g.major_id and a.colid=g.minor_idLeft join Sys.extended_properties F on D.id=f.class and f.minor_id=0Where b.name is not null--where d.name= ' table to query '--if you only query the specified table, add this conditionORDER BY A.id,a.colorderHow

1. Query all database names in the database:SELECT Name from Master. sysdatabases ORDER by Name2. Query all the table names in a database:SELECT name from SysObjects Where xtype= ' U ' ORDER by Name3. Query table structure information: 1 SELECT (case if A.colorder=1 then d.name else null end) Table name, 2 a.colorder field ordinal, a.name field name, 3 TY (a.id,a.name, ' isidentity ') =1 then ' √ ' else '

Label: 1. Query all database names in the database: SELECT Name from Master. sysdatabases ORDER by Name 2. Query all the table names in a database: SELECT name from SysObjects Where xtype= ' U ' ORDER by Name 3. Query table structure information: 1 SELECT (case if A.colorder=1 then d.name else null end) Table name, 2 a.colorder field ordinal, a.name field name, 3 Erty (a.id,a.name, ' isidentity ') =1 then

sysobjectswhere xtype = ' u 'Open C2DECLARE @c2 varchar (8000)FETCH NEXT from C2 to @c2while (@ @fetch_status =0)BeginEXEC (@c2)FETCH NEXT from C2 to @c2EndClose C2DEALLOCATE C2--3. Enabling FOREIGN KEY constraintsDECLARE C1 Cursor FORSelect ' ALTER TABLE [' + object_name (parent_obj) + '] Check constraint [' +name+ ']; ‘From sysobjectswhere xtype = ' F 'Open C1DECLARE @c1 varchar (8000)FETCH NEXT from C1 to @c1while (@ @fetch_status =0)BeginEXEC (@c1)FETCH NEXT from C1 to @c1EndClose C1DEALLOC

Tool: PlsqlSteps:Log in to Plsql, open the table, then click Tools--Export user objects, select the exported content to specify the export location, OK650) this.width=650; "src=" Https://s5.51cto.com/wyfs02/M00/8E/5A/wKioL1i-cTizWRy9AANCKmLRg_E035.png "style=" float : none; "title=" Fff.png "alt=" Wkiol1i-ctizwry9aanckmlrg_e035.png "/>650) this.width=650; "src=" Https://s1.51cto.com/wyfs02/M00/8E/5C/wKiom1i-cTnDXt56AAASQzzhJtI514.png "style=" float : none; "title=" Qq20170307163931.png "alt=" Wk

SQL Union and SQL UNION ALL usageSQL UNION operatorThe UNION operator is used to combine the result set of two or more SELECT statements.Note that the SELECT statement inside the UNION must have the same number of columns. The column must also have a similar data type . Also, the order of the columns in each SELECT statement must be the same.SQL UNION SyntaxSELEC

SQL union and SQL Union all usage SQL Union operator The Union operator is used to merge the result sets of two or more select statements. Note that the SELECT statement inside the Union must haveSame quantity. Columns must also haveSimilar data types. In additionSequenceMust be the same.

SQL Union UsageSQL Union and SQL UNION ALL usageSQL UNION operator The UNION operator is used to combine the result set of two or more SELECT statements. Notice that the SELECT statement inside the UNION must have the same number of columns. The column must also have a similar data type. Also, the order of the columns in each SELECT statement must be the

In general, we can use connect to server in SQL Server Management studio to query and try to connect all available SQL Server instances in the local network, such: In Visual Studio, you can also use tools> connect to database to query and connect available SQL Server instances in the local network. In addition,

How to display all SQL statements in the program file and the running time of each SQL statement? Php + mysql. if you want to analyze the SQL running status, read the "TheSlowQueryLog" section in the mysql manual and analyze the log file, in the database connection class, how does one display

One SQL statement interview question: for students who take all courses, SQL statements For a job interview a few days ago, there was an SQL question: three tables are provided: students, courses, and scores. A seemingly simple problem made me difficult. I changed it and changed it, painted it and scratched my ears. Be

T-SQL statements and so on, add as needed, add only get the T-SQL statement function that is executing) Traceserver trace = new Traceserver ();Trace. Initializeasreader (Conninfo, "MYTDF.TDF");while (trace. Read ()){statements;Console.WriteLine (trace["TextData"]);}Console.read ();Trace. Close (); All code: Using System;Using System.Collections.Generic;Using Sy

Label:Alias (aliases) eg (using table name aliases): Select Po.orderid,p.lastname,p.firstname from persons as p,product_orders as Po where p.lastname= ' Adams ' and p.firstname= ' John ' (using aliases) Select Product_orders.orderid,persons.lastname,persons.firstname from Persons,product_orders where persons.lastname = ' Adams ' and Persons.firstname= ' John ' (Do not use aliases) eg (using a column name alias): Select LastName as family,firstname as name from persons

Displays information about all tables or views in a database of an SQL Server. The difference between SQL Server 2000 and 2005 lies in the red part. The following statement is used to obtain information about all tables. Replace "U" with "v" with "U" to obtain information about all