sql primary key autoincrement

contains only the table foreign key relationships from the source database Step is approximately the same as Step 1, the last step is set to the oppositeRed box, set the Write foreign key script to True, and the other options are the opposite of those set in step 1. Click the "OK" button to generate the script and save it as "Originaldatastructureonlywithfk.sql". 　　Step 6: Import

SQL statement query table name/column name/primary key/Auto grow value in database ----A table created by a user in a query database ----JSJ01 as database name Select name tablename from JSJ01. sysobjects where type= ' U ' and name not in (' dtproperties ') --field information in the query table ---docs as table name ----SELECT * from syscolumns where id = o

Tags: des http io ar os sp strong file dataThe Selectkey element of the Ibatis sqlmap configuration file has a type attribute that allows you to specify pre or post representation before generation (pre) or the epigenetic (post).Oracle SettingsXML code insert id="insertproduct-oracle" parameterclass="com.domain.Product"> selectkey resultclass="int" keyproperty="id" type="pre"> selectkey> Insert> MS SQL Server ConfigurationXM

Tags: Data blog ted before SQL Arch Company let policy configuration SQL Server command: Select NewId (), you can get the native UUID value of the SQL Server database, so we can write this instruction to MyBatis's primary key generation policy configuration Selectkey. As fol

Label:In writing SQL, we often encounter such a problem. Every time you insert, you have to judge whether the data table already exists in this data, the so-called same data, except the primary key all columns are the same, no insert, there is update. In this situation, we do not know whether this column exists, so the simple insertion and update are problematic,

1. Create a new tableCREATE TABLEYsb_log (ID Number(8)Primary Key not NULL, Tbdatevarchar( -)NULL, Tb_timevarchar( -) not NULL, Tblogvarchar( -) not NULL, Tbreorvarchar2( -)NULL, BSvarchar( -) not NULL );In Oracle, sequence is the so-called serial number, which is automatically incremented each time it is taken, and is typically used where serial numbers need to be sorted.2. Create a self-incrementCreate

Label:exenotseledropclass prerop CREATE TABLE create sequence --CREATE TABLE Bonus_benchmark_ VALUE---------------------------------------------------------------declare num number; Begin select COUNT (1) into NUM from user_tables WHERE table_name = UPPER (' Bonus_benchmark_value '); If Num>0 then execute immediate ' drop table Bonus_benchmark_value '; End If; end;/--------------------------------Table structure for bonus_benchmark_value------------------------------ CREATE TABLE bonus

, don't worry. The time precision of the last 6 bytes can reach 1/300 seconds, the possibility that two COMB data types are identical is that the first 10 bytes of the two guids generated in these 1/300 seconds are identical, which is almost impossible! In SQLThe SQL command is used to implement this idea: DECLARE @ aGuidUNIQUEIDENTIFIER SET @ aGuid = CAST (NEWID () as binary (10 )) + CAST (GETDATE () as binary (6) as uniqueidentifier) After testing,

1, deletion of primary key ALTER TABLE tablename Drop Primary_key executes the above SQL to delete the primary key, and if it is unsuccessful, ALTER TABLE tablename drop CONSTRAINTS COLUMN CASCADE; --delete constraint ALTER TABLE tablename DISABLE primary_column;--Set t

------------------------------------------------PK_TEST_IDP TEST ENABLEDFrom the above, we have created a primary key constraint named "pk_test_id" whose current state is valid.Sql> Select Index_name,uniqueness,table_name,status from user_indexes where table_name= ' TEST '; index_nameuniqueness table_name STATUS----------------------------------------------------------------Pk_test_idunique TEST VALIDFrom t

call to LAST_INSERT_ID () on the MYCAT layer will not return the result.The correct configuration is as follows:1) MySQL definition self-increment primary key----------------------------------------------Create a test table--------------------------------------------CREATE TABLEIF not EXISTStb_auto_increment (IDINT not NULL PRIMARY KEYAuto_increment,nameVARCHA

problem should be based on the internal implementation of mysql to avoid introducing new problems. This bug I colleague has submitted to the community, http://bugs.mysql.com/73563, you can look. The problem of setting primary key auto-increment in mysql Database modification mysql Character Set: mysql character set can be set when mysql is installed. Generally, use utf8 Character Set 1 to view the

Hibernate primary key generation policy and hibernate primary key policy Hibernate Primary Key Generation Policy 1. Automatic growth of identity Applicable to MySQL, DB2, and ms SQL Se

composite primary keys) 1. Create an experiment table. test1 is a single primary key with one column, test2 is the Union primary key with two columns, and test3 is the Union primary key