大约有 37,000 项符合查询结果（耗时：0.0390秒） [XML]
In where shall I use isset() and !empty()
...nd the answer is:
$var = "";
var_dump(isset($var));
The type comparison tables in PHP’s manual is quite handy for such questions.
isset basically checks if a variable has any value other than null since non-existing variables have always the value null. empty is kind of the counter part to iss...
How to scroll to specific item using jQuery?
I have a big table with vertical scroll bar.
I would like to scroll to a specific line in this table using jQuery/Javascript.
...
What is a “static” function in C?
...) { return 0; }
static int sf() { return 0; }
and disassemble the symbol table with:
readelf -s main.o
the output contains:
Num: Value Size Type Bind Vis Ndx Name
5: 000000000000000b 11 FUNC LOCAL DEFAULT 1 sf
9: 0000000000000000 11 FUNC GLOBAL DEFAULT...
SQL command to display history of queries
...
For MySQL > 5.1.11 or MariaDB
SET GLOBAL log_output = 'TABLE';
SET GLOBAL general_log = 'ON';
Take a look at the table mysql.general_log
If you want to output to a log file:
SET GLOBAL log_output = "FILE";
SET GLOBAL general_log_file = "/path/to/your/logfile.log"
SET GLOBAL g...
How to parse JSON data with jQuery / JavaScript?
... Thank you. helpful answer. How to get specified column value in a db table ?
– PHPFan
Aug 3 '19 at 9:51
@PHPFan ...
How to unit test an object with database queries
...
I know this is old but what about creating a duplicate table to the one that is in the DB already. That way you can confirm DB calls work?
– bretterer
Oct 3 '12 at 3:59
...
Removing index column in pandas when reading a csv
...
Using df.to_sql("table",cursor,if_exists="append",index=False) also fixes the sqlite error sqlite3.OperationalError: table message has no column named index
– Anna
Jun 3 '18 at 0:55
...
PSQLException: current transaction is aborted, commands ignored until end of transaction block
...
I got this error using Java and PostgreSQL doing an insert on a table. I will illustrate how you can reproduce this error:
org.postgresql.util.PSQLException: ERROR:
current transaction is aborted, commands ignored until end of transaction block
Summary:
The reason you get this error is...
How does the socket API accept() function work?
...g on the Server IP maintains a database (meaning I don't care what kind of table/list/tree/array/magic data structure it uses) of active sockets and listens on the Server Port. When it receives a message (via the server's TCP/IP stack), it checks the Client IP and Port against the database. If the...
UITableViewHeaderFooterView: Unable to change background color
I'm trying to change the background color of UITableViewHeaderFooterView. Although the view is appearing, the background color remains the default color. I'm getting a log from xcode saying:
...