update query in sql developer

I,Create a table:Create Table 'flower '('Id' int (11) not null auto_increment,'Color' varchar (255) default null,Primary Key ('id ')) Engine = InnoDB auto_increment = 6 default charset = Latin1Insert the following data:1 blue2 red3 blue4 red5 blueNow we need to use an SQL statement to calculate the number of all red and blue colors,It can be as follows:SelectSum (case when color = 'red' then 1 else 0 end) as 'red ',Sum (case when color = 'blue' then 1

= (Select distinctb.scrm_rptpnt_processed frompntmall_rptpoint_detail_tmp b where a.pntmall_rptpnt_id=b.pntmall_rptpnt _id) wherea.pntmall_rptpnt_id in (select b.pntmall_rptpnt_id frompntmall_rptpoint_detail_tmp b)The optimized SQL reaches the second level to meet customer needs.Summarize the situation that does not follow the index:1, the condition field selectivity is weak, the result set of the detection is large, do not go index;2. Where condition

Tags: color nbsp span rowid rom Resolution table name right clickWhen we operate on an Oracle database, we sometimes want to manipulate some of the data after we have finished querying the results, and when we click Edit (a lock flag), we are prompted with the error in the above question: These query results are not updatable, please use ROWI or select ... For update to get updatable results. We can use two

Oracle Notes (11) Build table, update, query comprehensive exercisesThere is a database of information about a student sports meeting, and the following tables are saved: Athlete Sporter (athlete number Sporterid, athlete name name, athlete sex sex, Affiliation department number Department) Item Item (Project number itemid, project name ItemName, Project match location) Score Grade (athlete

, ThinkPHP enables dynamic queries. 1. getBy dynamic query // Find the data for email = xiaoin@163.com $ User = M ('user '); Var_dump ($ user-> getByemail ('xiaoxin @ 163.com ')); 2. getFieldBy dynamic query // Get the corresponding id value through user $ User = M ('user '); Var_dump ($ user-> getFieldByUser ('lufei ', 'id ')); 8. SQL

WHERE job = 'manager '; The execution efficiency of merge queries is much higher than that of logical queries such as and or. 5.10 insert data using a subquery SQL> CREATE TABLE myEmp (empID number (4), name varchar2 (20), sal number (6), job varchar2 (10), dept number (2 )); create an empty table first; SQL> INSERT INTO myEmp (empID, name, sal, job, dept) SELECT empno, ename, sal, job, deptno FROM emp WHE

Link to the comprehensive exercise for creating, updating, and querying Oracle notes (11): Oracle notes (1) Introduction to Oracle and installation of explain (2) SQLPlus command http://www.bkjia.com/database/201209/154051.html#oraclenotes (3) scott user's table structure partition (4) simple query, restricted query, data sorting http://www.bkjia.com/database/201209/154054.html?oraclenote (5) Single Row fun

Tags: val operation data operation IAR Comma ICA multiple span insertSometimes data operations are required, and data is updated if there is data, and no data is inserted. The previous practice is to query, and then based on the query results to judge, to perform the INSERT or update operationThere is actually an on DUPLICATE KEY

Tags: style color using strong data for problem codesWhen we operate on an Oracle database, we sometimes want to manipulate some of the data after we have finished querying the results, and when we click Edit (a lock flag), we are prompted with the error in the above question: These query results are not updatable, please use ROWI or select ... For update to get updatable results. We can use two solutions a

Today, using the Pl/sql tool to manipulate table data in an Oracle database, you can not modify it, as prompted on the prompt box, resolved as follows: Select T.id,t.title,t.content,t.cperson,t.cdate,t.sdate from T_notice t for update; Now the query out of the data click Modify can be normal to modify, after the completion of the modification can not forget t

Scenario: In a previous Test sermon, a colleague directly generated an INSERT statement using NAVICAT from the lookup results, supporting the batch generation of statements.Application scenarios: Automation, performance testing initialization data . Directly from the existing library to query the required data content, and then generate the corresponding INSERT statement, inserted into the corresponding test target database, reduce the manual hand int

Name= ' Zhang San ');Step three: Find the athlete number based on this item numberSelect SporteridFrom gradeWhere Itemid in (Select ItemidFrom gradeWhere Grade.sporterid= (Select SporteridFrom SporterWhere Name= ' Zhang San '));Fourth step: Find athlete information according to athlete numberSELECT *From Sporterwhere Sporterid in (Select SporteridFrom gradeWhere Itemid in (Select ItemidFrom gradeWhere Grade.sporterid= (Select SporteridFrom SporterWhere Name= ' Zhang San ')))and name! = ' Zhang

The following table is saved in a database with information about a student sports meeting:Athlete sporter (athlete ID: sporterid, athlete name, athlete gender sex, department)Project item (Project No. itemid, project name itemname, project competition location)Score grade (athlete id, Project id itemid, point mark) Use SQL statements to complete the following functions: 1. Create a table and add constraints on the corresponding fields;Define the prim

Advanced query technology is mainly related to multiple tables linked query technology, embedded SELECT statement subquery technology, the combination of multiple queries combined technology. 1. Connection Query You need to retrieve data from two or more tables at the same time. A link allows you to retrieve data from two tables or more than two tables at the s