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In MySQL, how to copy the content of one table to another table within the same database?

... INSERT INTO TARGET_TABLE SELECT * FROM SOURCE_TABLE; EDIT: or if the tables have different structures you can also: INSERT INTO TARGET_TABLE (`col1`,`col2`) SELECT `col1`,`col2` FROM SOURCE_TABLE; EDIT: to constrain this.. INSERT INTO TARGET_TAB...
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Insert into … values ( SELECTFROM … )

... Try: INSERT INTO table1 ( column1 ) SELECT col1 FROM table2 This is standard ANSI SQL and should work on any DBMS It definitely works for: Oracle MS SQL Server MySQL Postgres SQLite v3 Teradata DB2 Sybase Vertica HSQLDB H2 AWS RedShift SA...
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Row Offset in SQL Server

... I would avoid using SELECT *. Specify columns you actually want even though it may be all of them. SQL Server 2005+ SELECT col1, col2 FROM ( SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum FROM MyTable ) AS MyDerivedTable...
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How do you create a random string that's suitable for a session ID in PostgreSQL?

...sion verification using PostgreSQL. I know I can get a random number with SELECT random() , so I tried SELECT md5(random()) , but that doesn't work. How can I do this? ...
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How to deal with SQL column names that look like SQL keywords?

...ange the name because I didn't make it. Am I allowed to do something like SELECT from FROM TableName or is there a special syntax to avoid the SQL Server being confused? ...
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Count work days between two dates

... For workdays, Monday to Friday, you can do it with a single SELECT, like this: DECLARE @StartDate DATETIME DECLARE @EndDate DATETIME SET @StartDate = '2008/10/01' SET @EndDate = '2008/10/31' SELECT (DATEDIFF(dd, @StartDate, @EndDate) + 1) -(DATEDIFF(wk, @StartDate, @EndDate) *...
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How to get the sizes of the tables of a MySQL database?

...he size of a table (although you need to substitute the variables first): SELECT table_name AS `Table`, round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB` FROM information_schema.TABLES WHERE table_schema = "$DB_NAME" AND table_name = "$TABLE_NAME"; or this query ...
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How to set caret(cursor) position in contenteditable element (div)?

... In most browsers, you need the Range and Selection objects. You specify each of the selection boundaries as a node and an offset within that node. For example, to set the caret to the fifth character of the second line of text, you'd do the following: function s...
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What is the most efficient/elegant way to parse a flat table into a tree?

...port recursive queries in standard syntax. WITH RECURSIVE MyTree AS ( SELECT * FROM MyTable WHERE ParentId IS NULL UNION ALL SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id ) SELECT * FROM MyTree; I tested recursive queries in MySQL 8.0 in my presentation Recursive ...
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How to subtract 30 days from the current datetime in mysql?

... SELECT * FROM table WHERE exec_datetime BETWEEN DATE_SUB(NOW(), INTERVAL 30 DAY) AND NOW(); http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-add ...