inpro comm

) from emp;5. SQL and SQL * PlusYou can use SQL * Plus:Describes the table structure, edits SQL statements, and executes SQL statements. Save the SQL statement in the file and save the SQL statement execution result in the file. Execute the statement in the saved file. Load the text file into the SQL * Plus editing window.6 Other comparison operationsUse the LIKE operation to select a similar value;The selection condition can contain characters or numbers: % Represents zero or multiple character

of rows selected is displayed.14. set feedback on; displays the number of rows selected during execution.15. set heading off; cancel the header information of the field16. set heading on; displays the header information of the field.17. set trimout on;18. set trimout off;Ii. query table:1. select * from tabs; query system table2. select table_name from user_tables; Name of the table under the current user3. desc table name query table structure4. set linesize 120 to set the Row Height5. col nam

characters (any character); _ represents one character; '%' and '-' can be used at the same time; you can use the ESCAPE identifiers to select the '%' and '_' symbols. To avoid special symbols, use ESCAPE characters. For example, convert [%] to [\ %], [_] to [\ _], and then add [ESCAPE '\']. Use IS (NOT) NULL determines the NULL value. Example: Select * from emp where sal between 1000 and 2000; empno ename job mgr hiredate sal comm deptno ----------

special characters are used in the alias or the output is case-insensitive. Format: SELECT | [[AS] ],... FROM ; Example: select empno, ename "Ename", sal * 12 "annual salary" from emp; Select empno as employee ID, ename employee name, sal * 12 "annual salary" from emp; Note: as can be skipped. Aliases can be enclosed in double quotation marks. If the alias does not contain special characters, double quotation marks can be omitted. If the alias conta

(commonly used) is returned)For example, if an employee has no commission, 0 is displayed; otherwise, the Commission is displayed.Select comm, nvl (comm, 0) from emp;Nullif (ex1, ex2 ):Returns NULL if the value is equal. Otherwise, the first value is returned.For example, if the salary is equal to the Commission, it is blank; otherwise, the salary is displayed.Select nullif (sal,

-----------------------------------Database write Stored Procedure Create proc usp_pagesplit2 @ pageindex int, @ pagesize int, @ pagecount int output, @ records int outputasbeginselect @ pagecount = count (*) from DBO. sset @ records = ceiling (@ pagecount/@ pagesize) Select * from (select row_number () over (order by SnO DESC) as num, * From DBO. s) as twhere T. num between (@ pageIndex-1) * @ pagesize + 1 and @ pageindex * @ pagesize enddeclare @ PC int, @ RC intexec usp_pagesplit2 2, 2, 3,

call the stored procedure for data insertion: // Call the stored procedure to insert a record bool cdbtestappdlg: insertrecord () {cadoparameter param1, param2, param3; cadocommand comm; If (conntodb () {comm. setconnection (m_pconnection); param1.setsize (20); param1.setname ("c_name"); param1.setdirection (adparaminput); param1.settype (advarchar); // varchar2param1. setvalue (cstring) "hello113"); // ty

/// /// Stored procedure execution function/// /// /// /// /// Public void execstoredprocedure (string strspname, hashtable HT, string [] strparameterarray){Sqlcommand comm = new sqlcommand (strspname, Conn );Comm. commandtype = commandtype. storedprocedure; Idictionaryenumerator htenumerator = Ht. getenumerator ();While (htenumerator. movenext ())Comm. Paramet

] 1) Select to_char (sysdate) S1, To_char (sysdate, 'yyyy-mm-dd') S2, To_char (sysdate, 'yyyy') S3, To_char (sysdate, 'yyyy-mm-dd hh12: MI: ss') S4, To_char (sysdate, 'hh24: MI: ss') S5, To_char (sysdate, 'day') S6 from dual; 2) Select Sal, to_char (SAL, '$99999') N1, to_char (SAL, '$99,999') N2 from EMP 2. to_date () [convert the character type to the date type] Insert into EMP (empno, hiredate) values (8000, to_date ('2017-10-10 ', 'yyyy-mm-dd ')); 3. to_number () to numeric type Select to_num

Using system; Using system. runtime. interopservices; Namespace nativedll {/// /// Summary of SerialPort./// Public class SerialPort{# Region declares the APIS related to serial call to be referenced// Win32 API ConstantsPrivate const uint generic_read = 0x80000000;Private const uint generic_write = 0x40000000;Private const int open_existing = 3;Private const int invalid_handle_value =-1;Private const int maxblock = 4096; Private const uint purge_txabort = 0x0001; // kill the pendin

=" 115 "/> Important: * The TO_NUMBER () function is not considered; * The TO_CHAR () function is the focus; * The TO_DATE () function is the secondary focus. 5-General functions (CORE) There are two common functions: NVL) and DECODE (). These two functions are Oracle's own special functions; 1. NVL () function, processing null Example 26:: Query the total annual salary of each employee. SQL> SELECT ename, sal, comm, (sal +

Compare two files in linux, and compare two files in linux Recently, I am writing a script to compare the configuration IP address of the/etc/dhcpd file with the IP address obtained by arp-n. This requires finding out the difference between the two output files-that is, there is no part in file 1 but in file 2, or there is a part in file 2 but not in file 1. There are four common methods on the Internet to implement this function. However, in actual tests, it is found that the results of one met

Java serial port communication API description Java serial port communication Java serial communication API descriptionJava Serial CommunicationJava provides the communicationapi (included in the javax. Comm package) for controlling various external devices in a machine-independent manner. Communications API is an extension of standard Java, which is not included in Java API. Therefore, you must first download this extension class library fro

/html/[[email protected] html]# lsindex.htmlAt this point, according to normal situation, because there is a index.html page in the HTML directory, if we refresh the browser page, we should jump to the index.html pageBut the fact that we found that the page is still on this test page, exactly why? This is related to our selinux security strategy, we can go to /var/log/audit This directory to view audit.log This file, to find out the error message[[emailprotected] html]# tail/var/log/audit/audit.

1. General method of calling stored procedures Let's assume that there is a stored procedure dt_users in SQL Server: CREATE PROCEDURE [dbo]. [Dt_users] As SELECT * from Users Return Go The first approach is to not use the command object, directly using the Recordset object Set Rs=server.createobject ("Adodb.recordset") Sql= "Exec dt_users" Rs.Open sql,conn,1,1 so you can The second approach is to take advantage of the Command object Set Comm=server.cr

1. General method of calling stored procedures Let's assume that there is a stored procedure dt_users in SQL Server: CREATE PROCEDURE [dbo]. [Dt_users] As SELECT * from Users Return Go The first approach is to not use the command object, directly using the Recordset object Set Rs=server.createobject ("Adodb.recordset") Sql= "Exec dt_users" Rs.Open sql,conn,1,1 so you can The second approach is to take advantage of the Command object Set Comm=server.cr

execution is displayed as ename. Only double quotes are given to it to show the following significant lowercase Null value Overview: Null values are invalid, unspecified, unknown, or unpredictable values. Null value is not equal to 0 or space For example: select Empno, ename, Sal, comm from emp;--the Comm properties of some records will show a blank, i.e. null value INSERT into student (age) VALUES (24

Copy Code code as follows: --Execution order from Where Select SELECT * FROM (select Sal as salary,comm as commission from EMP) x where salary--Draw Name Work as a Job Select Ename + ' Work as a ' +job as msg from EMP where deptno=10 --If the employee pay less than 2000 returns underpaid greater than or equal to 4k return OK between overpaid Select Ename,sal, Case when salWhen sal>=4000 then ' overpaid ' Else ' OK ' End From EMP --Ran

Stored procedure 1. General method of calling stored procedures Let's assume that there is a stored procedure dt_users in SQL Server: CREATE PROCEDURE [dbo]. [Dt_users] As SELECT * from Users Return Go The first approach is to not use the command object, directly using the Recordset object Set Rs=server.createobject ("Adodb.recordset") Sql= "Exec dt_users" Rs.Open sql,conn,1,1 so you can The second approach is to take advantage of the Command object Set Comm