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How to debug PDO database queries?
...ments to Rails, but that the benefit is much heavier in PostgreSQL than in MySQL. He said that this is because MySQL doesn't actually create the query plan until you execute the prepared query.
– Nathan Long
Jul 20 '11 at 13:46
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How do I create a PDO parameterized query with a LIKE statement?
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thanks. had similar issue with csharp + Mysql + ODBC using like it would not return any rows using "select * from table where column like '%?%';" but will if I do like you did "select * from table where column like ?;" and set the parameter string so: string frag =...
How do I check to see if a value is an integer in MySQL?
I see that within MySQL there are Cast() and Convert() functions to create integers from values, but is there any way to check to see if a value is an integer? Something like is_int() in PHP is what I am looking for.
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Where is a complete example of logging.config.dictConfig?
... # Default is stderr
},
},
'loggers': {
'': { # root logger
'handlers': ['default'],
'level': 'WARNING',
'propagate': False
},
'my.packg': {
'handlers': ['default'],
'level': 'INFO',
'...
Importance of varchar length in MySQL table
I have a MySQL table where rows are inserted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessar...
How to subtract 30 days from the current datetime in mysql?
How do I subtract 30 days from the current datetime in mysql?
8 Answers
8
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Is it a good idea to index datetime field in mysql?
...etime clause to select data. Is it a good idea to index datetime fields in mysql database?
2 Answers
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Dropping Unique constraint from MySQL table
How can I drop the "Unique Key Constraint" on a column of a MySQL table using phpMyAdmin?
10 Answers
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Maximum length of a table name in MySQL
What is the maximum length of a table name in MySQL?
4 Answers
4
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How to delete a column from a table in MySQL
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Here's a working example.
Note that the COLUMN keyword is optional, as MySQL will accept just DROP IsDeleted. Also, to drop multiple columns, you have to separate them by commas and include the DROP for each one.
ALTER TABLE tbl_Country
DROP COLUMN IsDeleted,
DROP COLUMN CountryName;
This...