大约有 40,000 项符合查询结果（耗时：0.0323秒） [XML]
How to do a regular expression replace in MySQL?
...
With MySQL 8.0+ you could use natively REGEXP_REPLACE function.
12.5.2 Regular Expressions:
REGEXP_REPLACE(expr, pat, repl[, pos[, occurrence[, match_type]]])
Replaces occurrences in the string expr that match the regular express...
What is the best place for storing uploaded images, SQL database or disk file system? [closed]
...
I have recently created a PHP/MySQL app which stores PDFs/Word files in a MySQL table (as big as 40MB per file so far).
Pros:
Uploaded files are replicated to backup server along with everything else, no separate backup strategy is needed (peace of min...
What columns generally make good indexes?
...er to use index */
Since "buyer_id" is referenced in the SELECT portion, MySQL will not use it to limit the chosen rows. Hence, there is no great need to index it. The below is another example little different from the above one:
SELECT
buyers.buyer_id, /* no need to index */
country.name /*...
MySQL: Sort GROUP_CONCAT values
...
Sure, see http://dev.mysql.com/doc/refman/...tions.html#function_group-concat:
SELECT student_name,
GROUP_CONCAT(DISTINCT test_score ORDER BY test_score DESC SEPARATOR ' ')
FROM student
GROUP BY student_name;
...
How to change the name of a Django app?
...E <oldAppName>_modelName RENAME TO <newAppName>_modelName. For mysql too I think it is the same (as mentioned by @null_radix)
(For Django >= 1.7) Update the django_migrations table to avoid having your previous migrations re-run: UPDATE django_migrations SET app='<NewAppName>' W...
Rename a table in MySQL
Renaming a table is not working in MySQL
16 Answers
16
...
Insert into … values ( SELECT … FROM … )
... struggle to remember the correct syntax for the SQL engine of the day ( MySQL , Oracle , SQL Server , Informix , and DB2 ).
...
Commands out of sync; you can't run this command now
I am trying to execute my PHP code, which calls two MySQL queries via mysqli, and get the error "Commands out of sync; you can't run this command now".
...
How do I get a raw, compiled SQL query from a SQLAlchemy expression?
...o %s or other variables waiting to be bound by the statement compiler or MySQLdb dialect engine, etc).
12 Answers
...
Checking for an empty field with MySQL
...)" and there's one record with null hotline but it doesn't match.I'm using MySQL 5.6
– Scott Chu
Apr 15 '16 at 10:16
...