Lower case column names when using SELECT
I'm using the Kohana framework and I need to convert column names to lowercase. I don't have control of the db table structure. I want to do the following:
SELECT LOWER(*) FROM .....
but MYSQL does not like that. Whats the proper way of outp开发者_StackOverflowutting the lower case column names if I don't know what the column names will be?
Found here http://dev.mysql.com/doc/refman/5.0/en/columns-table.html
SELECT LOWER(COLUMN_NAME)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'Table'
Below you can see both MSSQL and MySQL syntax for creating a dynamic query using the column results from the query above.
MSSQL Syntax
DECLARE @ColumnNames [nvarchar](1024)
SELECT @ColumnNames = COALESCE(@ColumnNames + ', ', '') + LOWER(COLUMN_NAME)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'Table'
DECLARE @Sql [nvarchar](1024) = 'SELECT ' + @ColumnNames + ' FROM Table ' --Remember to put spaces after SELECT and before FROM
EXEC(@Sql)
With this you are dynamically building your query and then executing it.
MySQL Syntax
SELECT @ColumnNames := GROUP_CONCAT(LOWER(COLUMN_NAME))
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'Table';
SET @Sql = CONCAT('SELECT ', @ColumnNames, ' FROM Table ');
PREPARE stmt1 FROM @Sql;
EXECUTE stmt1;
精彩评论