sqlite select if exists
If you have a table called memos that has two columns id and text you should be able to do like this: INSERT INTO memos(id,text) SELECT 5, 'text to insert' ... ,The EXISTS operator always evaluates to one of the integer values 0 and 1. If executing the SELECT statement specified as the right-hand operand of the ... ,Don't call fetchone() ; just treat the cursor as an iterator: for row in c.execute("SELECT name, age FROM ..."): name, age = row break else: print("not found"). ,If you desire to know the rowid , then using fetchall requires you to burrow through the ... for name in ('bar','foo'): cursor.execute("SELECT rowid FROM components .... exist = cursor.fetchone() if exist is None: ... # does not exist,INSERT INTO EVENTTYPE (EventTypeName) SELECT 'ANI Received' WHERE NOT EXISTS (SELECT 1 FROM EVENTTYPE WHERE EventTypeName = 'ANI ... ,To check that your table exists or not, you can use: SELECT * FROM sqlite_master WHERE name ='myTable' and type='table';. ,Introduction to SQLite EXISTS operator. The EXISTS operator is a logical operator that specifies a subquery to test for the existence of rows. In this syntax, the subquery is a SELECT statement that returns zero or more rows. If the subquery returns at le,select exists( select 1 from tbl_stats_assigned where username = 'abc' ); Assuming of course that your 1 and 0 are actually boolean values (which SQLite represents with one and zero just like MySQL). That should work in any SQL database and some e,The SQLite EXISTS condition is used in combination with a subquery and is considered "to be met" if the subquery returns at least one row. It can be used in a SELECT, INSERT, UPDATE, or DELETE statement. ,Though the documentation does not imply it, apparently the primary sqlite dev (Richard Hipp) has confirmed in the mailing list that EXISTS short circuits for you.
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 sqlite select if exists 相關參考資料
"Insert if not exists" statement in SQLite - Stack Overflow
If you have a table called memos that has two columns id and text you should be able to do like this: INSERT INTO memos(id,text) SELECT 5, 'text to insert' ... https://stackoverflow.com Android sqlite how to check if a record exists - Stack Overflow
The EXISTS operator always evaluates to one of the integer values 0 and 1. If executing the SELECT statement specified as the right-hand operand of the ... https://stackoverflow.com Check if a row exists in sqlite3? - Stack Overflow
Don't call fetchone() ; just treat the cursor as an iterator: for row in c.execute("SELECT name, age FROM ..."): name, age = row break else: print("not found"). https://stackoverflow.com How to check the existence of a row in SQLite with Python? - Stack ...
If you desire to know the rowid , then using fetchall requires you to burrow through the ... for name in ('bar','foo'): cursor.execute("SELECT rowid FROM components .... exist = c... https://stackoverflow.com How to do IF NOT EXISTS in SQLite - Stack Overflow
INSERT INTO EVENTTYPE (EventTypeName) SELECT 'ANI Received' WHERE NOT EXISTS (SELECT 1 FROM EVENTTYPE WHERE EventTypeName = 'ANI ... https://stackoverflow.com sqlite - how to check if table exists before completing inserts ...
To check that your table exists or not, you can use: SELECT * FROM sqlite_master WHERE name ='myTable' and type='table';. https://stackoverflow.com SQLite EXISTS - SQLite Tutorial
Introduction to SQLite EXISTS operator. The EXISTS operator is a logical operator that specifies a subquery to test for the existence of rows. In this syntax, the subquery is a SELECT statement that r... http://www.sqlitetutorial.net SQLite IF Exists Clause - Stack Overflow
select exists( select 1 from tbl_stats_assigned where username = 'abc' ); Assuming of course that your 1 and 0 are actually boolean values (which SQLite represents with one and zero just like ... https://stackoverflow.com SQLite: EXISTS Condition - TechOnTheNet
The SQLite EXISTS condition is used in combination with a subquery and is considered "to be met" if the subquery returns at least one row. It can be used in a SELECT, INSERT, UPDATE, or DELE... https://www.techonthenet.com Valid query to check if row exists in SQLite3 - Stack Overflow
Though the documentation does not imply it, apparently the primary sqlite dev (Richard Hipp) has confirmed in the mailing list that EXISTS short circuits for you. https://stackoverflow.com |