大约有 5,883 项符合查询结果(耗时:0.0330秒) [XML]

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Can I store images in MySQL [duplicate]

...need to save as a blob, LONGBLOB datatype in mysql will work. Ex: CREATE TABLE 'test'.'pic' ( 'idpic' INTEGER UNSIGNED NOT NULL AUTO_INCREMENT, 'caption' VARCHAR(45) NOT NULL, 'img' LONGBLOB NOT NULL, PRIMARY KEY ('idpic') ) As others have said, its a bad practice but it can be don...
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SQL query for finding records where count > 1

I have a table named PAYMENT . Within this table I have a user ID, an account number, a ZIP code and a date. I would like to find all records for all users that have more than one payment per day with the same account number. ...
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How do I flush the PRINT buffer in TSQL?

... on PRINT or RAISERROR and just load your "print" statements into a ##Temp table in TempDB or a permanent table in your database which will give you visibility to the data immediately via a SELECT statement from another window. This works the best for me. Using a permanent table then also serves a...
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When to add what indexes in a table in Rails

... end of the index. If you have a has_many :through relationship, your join table should have a unique index on both properties involved in the join as a compound key. If you fetch a record directly using a unique identifier such as username or email, that should be a unique index. If you fetch sets ...
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How to set Sqlite3 to be case insensitive when string comparing?

... can indicate that a column should be case insensitive when you create the table by specifying collate nocase in the column definition (the other options are binary (the default) and rtrim; see here). You can specify collate nocase when you create an index as well. For example: create table Test...
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Database development mistakes made by application developers [closed]

... auto-incrementing fields (SQL Server, MySQL, others) or sequences (most notably Oracle). In my opinion you should always use surrogate keys. This issue has come up in these questions: How do you like your primary keys? What's the best practice for primary keys in tables? Which format of primary...
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Large, persistent DataFrame in pandas

...le paths in_csv = '../data/my_large.csv' out_sqlite = '../data/my.sqlite' table_name = 'my_table' # name for the SQLite database table chunksize = 100000 # number of lines to process at each iteration # columns that should be read from the CSV file columns = ['molecule_id','charge','db','drugsnow'...
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How to filter NSFetchedResultsController (CoreData) with UISearchDisplayController/UISearchBar

...hedResultsController with a predicate to retrieve the data for the primary TableView. I want to make sure I'm on the right path before I change too much code. I'm confused because so many of the examples are array-based instead of CoreData. ...
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Border around tr element doesn't show?

... not render borders on tr , but it renders the border if the selector is table tr td . 1 Answer ...
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PostgreSQL LIKE query performance variations

...large variation in response times regarding LIKE queries to a particular table in my database. Sometimes I will get results within 200-400 ms (very acceptable) but other times it might take as much as 30 seconds to return results. ...