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How to execute a raw update sql with dynamic binding in rails
... MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("update table set f1=? where f2=? and f3=?")
st.execute(f1, f2, f3)
st.close
I'm not sure if there are other ramifications to doing this (connections left open, etc). I would trace the Rails code for a normal update to see what it'...
MySQL query to get column names?
I'd like to get all of a mysql table's col names into an array in php?
21 Answers
21
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How to import CSV file data into a PostgreSQL table?
...ite a stored procedure that imports data from a CSV file and populates the table?
18 Answers
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How to find gaps in sequential numbering in mysql?
We have a database with a table whose values were imported from another system. There is an auto-increment column, and there are no duplicate values, but there are missing values. For example, running this query:
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Difference Between One-to-Many, Many-to-One and Many-to-Many?
...one side and City is the many side. There will be a column state_id in the table cities.
In unidirectional, Person class will have List<Skill> skills but
Skill will not have Person person. In bidirectional, both
properties are added and it allows you to access a Person given a
skill( i.e. sk...
What's the difference between comma separated joins and join on syntax in MySQL? [duplicate]
For example if I were to have a table "Person" with a column "id" that references a column "id" in table "Worker"
5 Answers...
How to convert a string or integer to binary in Ruby?
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Picking up on bta's lookup table idea, you can create the lookup table with a block. Values get generated when they are first accessed and stored for later:
>> lookup_table = Hash.new { |h, i| h[i] = i.to_s(2) }
=> {}
>> lookup_table[1]...
SQL Server Insert if not exists
I want to insert data into my table, but insert only data that doesn't already exist in my database.
10 Answers
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Check if table exists and if it doesn't exist, create it in SQL Server 2008
I am writing a Stored procedure in SQL Server 2008.
I need to check if a table exists in the database. If it doesn't then I need to create it.
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Create unique constraint with null columns
I have a table with this layout:
4 Answers
4
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