大约有 40,000 项符合查询结果（耗时：0.0516秒） [XML]
Change auto increment starting number?
...foobar(moobar) values ("def");
INSERT INTO foobar(moobar) values ("xyz");
select * from foobar;
'10', 'abc'
'11', 'def'
'12', 'xyz'
This auto increments the id column by one starting at 10.
Auto increment in MySQL by 5, starting at 10:
drop table foobar
create table foobar(
id IN...
How do I create a new class in IntelliJ without using the mouse?
...with arrow keys, then press Alt+Insert.
Another useful shortcut is View | Select In (Alt+F1), Project (1), then Alt+Insert to create a class near the existing one or use arrow keys to navigate through the packages.
And yet another way is to just type the class name in the existing code where you w...
How to perform Single click checkbox selection in WPF DataGrid?
...ck the check box. It should get checked.
But, it takes two click to get selected, for first click the cell is getting selected, for the second clicks the check box is getting checked. How to make the check box to get checked/unchecked with a single click.
...
MySQL convert date string to Unix timestamp
...
Here's an example of how to convert DATETIME to UNIX timestamp:
SELECT UNIX_TIMESTAMP(STR_TO_DATE('Apr 15 2012 12:00AM', '%M %d %Y %h:%i%p'))
Here's an example of how to change date format:
SELECT FROM_UNIXTIME(UNIX_TIMESTAMP(STR_TO_DATE('Apr 15 2012 12:00AM', '%M %d %Y %h:%i%p')),'%m-%d-...
Want to find records with no associated records in Rails
... get everyone with no friends in the first case:
Person.where('id NOT IN (SELECT DISTINCT(person_id) FROM friends)')
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Are nested transactions allowed in MySQL?
...Y) ENGINE=InnoDB;
START TRANSACTION;
INSERT
INTO t_test
VALUES (1);
SELECT *
FROM t_test;
id
---
1
SAVEPOINT tran2;
INSERT
INTO t_test
VALUES (2);
SELECT *
FROM t_test;
id
---
1
2
ROLLBACK TO tran2;
SELECT *
FROM t_test;
id
---
1
ROLLBACK;
SELECT *
FROM ...
Oracle find a constraint
...
select * from all_constraints
where owner = '<NAME>'
and constraint_name = 'SYS_C00381400'
/
Like all data dictionary views, this a USER_CONSTRAINTS view if you just want to check your current schema and a DBA_CONSTRA...
How do I add a foreign key to an existing SQLite table?
...n step 8 below. One way to
do this is to run a query like the following: SELECT type, sql FROM
sqlite_master WHERE tbl_name='X'.
Use CREATE TABLE to construct a new table "new_X" that is in the
desired revised format of table X. Make sure that the name "new_X"
does not collide with any exi...
How do I join two SQLite tables in my Android application?
...
You need rawQuery method.
Example:
private final String MY_QUERY = "SELECT * FROM table_a a INNER JOIN table_b b ON a.id=b.other_id WHERE b.property_id=?";
db.rawQuery(MY_QUERY, new String[]{String.valueOf(propertyId)});
Use ? bindings instead of putting values into raw sql query.
...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...