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What is the most efficient/elegant way to parse a flat table into a tree?
Assume you have a flat table that stores an ordered tree hierarchy:
14 Answers
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Table is marked as crashed and should be repaired
...an use the command (there must be ample space for the mysql files)
REPAIR TABLE `<table name>`;
for repairing individual tables
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Unique constraint on multiple columns
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By using the constraint definition on table creation, you can specify one or multiple constraints that span multiple columns. The syntax, simplified from technet's documentation, is in the form of:
CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ]
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Declare variable in table valued function
How can I declare a variable in a table valued function? (like in my title)
1 Answer
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How to make Sequelize use singular table names
I have an model called User but Sequelize looks for the table USERS whenever I am trying to save in the DB. Does anyone know how to set Sequelize to use singular table names? Thanks.
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Simple way to transpose columns and rows in SQL?
...VOT and then an aggregate function with a CASE statement to PIVOT:
Create Table:
CREATE TABLE yourTable([color] varchar(5), [Paul] int, [John] int, [Tim] int, [Eric] int);
INSERT INTO yourTable
([color], [Paul], [John], [Tim], [Eric])
VALUES
('Red', 1, 5, 1, 3),
('Green', 8, 4, 3, 5),...
Repeat each row of data.frame the number of times specified in a column
...ndRows(df, "freq")
Simple syntax, very fast, works on data.frame or data.table.
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
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Entity Framework: table without primary key
...That's fine, I suppose, but keep in mind that the OP asked about mapping a table without a primary key, not a view. The answer is still the same. Working around the EF's need to have a PK on tables is a bad idea from the standpoint of manageability, data integrity, and performance.
Some have comm...
Rails: Adding an index after adding column
Suppose I created a table table in a Rails app. Some time later, I add a column running:
5 Answers
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Get the new record primary key ID from MySQL insert query?
Let's say I am doing a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key .
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