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How do I iterate through table rows and cells in JavaScript?
If I have an HTML table...say
9 Answers
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Delete duplicate rows from small table
I have a table in a PostgreSQL 8.3.8 database, which has no keys/constraints on it, and has multiple rows with exactly the same values.
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How to Store Historical Data
...y to store historical data. Currently, for some systems, I use a separate table to store historical data, and I keep an original table for the current, active record. So, let's say I have table FOO. Under my system, all active records will go in FOO, and all historical records will go in FOO_Hist...
How do I dump the data of some SQLite3 tables?
How do I dump the data, and only the data, not the schema, of some SQLite3 tables of a database (not all the tables)?
The dump should be in SQL format, as it should be easily re-entered into the database later and should be done from the command line. Something like
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Altering column size in SQL Server
How to change the column size of the salary column in the employee table from numeric(18,0) to numeric(22,5)
6 Answe...
MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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How to randomly select rows in SQL?
I am using MSSQL Server 2005. In my db, I have a table "customerNames" which has two columns "Id" and "Name" and approx. 1,000 results.
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How to reset a single table in rails?
...rd::Base.connection.execute("DELETE from sqlite_sequence where name = 'yourtablename'")
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Postgres and Indexes on Foreign Keys and Primary Keys
...ys? How can I tell? Is there a command that will return all indexes on a table?
7 Answers
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SQL - many-to-many table primary key
...is guaranteed unique (assuming your col1 and col2 values in the referenced tables are unique) and a separate index on (col2,col1) will catch those cases where the opposite order would execute faster. The surrogate is a waste of space.
You won't need indexes on the individual columns since the table...