1、创建简单视图 create view if not exists View_Corporate as select * from corporate where corid > 1 2、创建临时视图 create temp view tempView_Corporate as select * from corporate where corid > 1 五、删除视图 drop view if exists View_Corporate; 六、索引的创建 1、该索引基于corporate表的cor...
sqlite> CREATE VIEW testview AS SELECT * FROM testtable WHERE first_col > 100; 2. 创建临时视图: sqlite> CREATE TEMP VIEW tempview AS SELECT * FROM testtable WHERE first_col > 100; 3. "IF NOT EXISTS"从句: sqlite> CREATE VIEW testview AS SELECT * FROM testtable WHERE first_col > 10...
sqlite>CREATEVIEWtestviewASSELECT*FROMtesttableWHEREfirst_col > 100; Error:tabletestview already exists sqlite>CREATEVIEWIFNOTEXISTS testviewASSELECT*FROMtesttableWHEREfirst_col > 100; 五、删除视图: 该操作的语法和删除表基本相同,因此这里只是给出示例: sqlite>DROPVIEWtestview; sqlite>DROPVIEWtestview;...
sqlite> CREATE VIEW IF NOT EXISTS COMPANY_VIEW (VID, VNAME, VAGE) AS ...> SELECT ID, FIRSTNAME, AGE ...> FROM OLD_COMPANY; Run Time: real 0.004 user 0.000252 sys 0.001079 sqlite> SELECT * FROM COMPANY_VIEW; VID VNAME VAGE --- --- --- 1 Paul 32 2 Allen 25 3 Teddy 23 4 ...
SQLite实现ifnotexist类似功能的操作 需要实现：if not exists(select * from ErrorConfig where Type='RetryWaitSeconds')begin insert into ErrorConfig(Type,Value1)values('RetryWaitSeconds','3')end 只能⽤：insert into ErrorConfig(Type,Value1)select 'RetryWaitSeconds','3'where not exists(select * from...
CREATEVIEWwatch_singleASSELECTDISTINCTwatch_item.[watchid],watch_item.[itemid]FROMwatch_item; 1. 上面这条SQL语句执行后会显示成功,但是实际上除了 复制 SELECTCOUNT(*)FROM[watch_single ]WHEREwatch_ single.watchid = 1; 1. 能执行之外是无法执行其他任何语句的。其原因在于建立视图的时候指定了字段所在...
create viewifnot exists hn_items_fieldsasselectjson_extract(data,'$.created_at')ascreated_at,json_extract(data,'$.title')astitle,json_extract(data,'$.url')asurl,json_extract(data,'$.author')asauthor,json_extract(data,'$.points')aspoints,json_extract(data,'$.comment_text')ascomment_te...
create_tb_cmd=''' CREATE TABLE IF NOT EXISTS USER (NAME TEXT, AGE INT, SALARY REAL); ''' conn.execute(create_tb_cmd) 4.在SQLite数据库中如何列出所有的表和索引 在一个 C/C++ 程序中(或者脚本语言使用 Tcl/Ruby/Perl/Python 等) 你可以在一个特殊的名叫 SQLITE_MASTER 上执行一个SELECT查询以...
CREATE VIEW DELETE DETACH DATABASE DROP INDEX DROP TABLE DROP TRIGGER DROP VIEW END TRANSACTION EXPLAIN expression INSERT ON CONFLICT clause PRAGMA REPLACE ROLLBACK TRANSACTION SELECT UPDATE 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. ...
(cFileName,&_db);if(result!=SQLITE_OK){// 打开失败NSLog(@"打开数据库失败");return;}NSLog(@"打开数据库成功");// 创建表constchar*sql="CREATE TABLE IF NOT EXISTS t_students(id integer PRIMARY KEY AUTOINCREMENT,name text NOTNULL,age integer NOTNULL);";char*errMsg=NULL;result=sqlite3_...