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Does order of where clauses matter in SQL?
Let's say I have a table called PEOPLE having 3 columns ID, LastName, FirstName , none of these columns are indexed.
LastName is more unique, and FirstName is less unique.
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An efficient compression algorithm for short text strings [closed]
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Check out Smaz:
Smaz is a simple compression library suitable for compressing very short
strings.
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What is the “owning side” in an ORM mapping?
... example of two entities mapped without declaring a owning side:
@Entity
@Table(name="PERSONS")
public class Person {
@OneToMany
private List<IdDocument> idDocuments;
}
@Entity
@Table(name="ID_DOCUMENTS")
public class IdDocument {
@ManyToOne
private Person person;
}
From a...
A dependent property in a ReferentialConstraint is mapped to a store-generated column
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Is it possible that you defined a bad column relation between your tables? different columns and one was set as autonumeric.
It happened to me.
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List of all index & index columns in SQL Server DB
...This query's getting pretty close to what you're looking for:
SELECT
TableName = t.name,
IndexName = ind.name,
IndexId = ind.index_id,
ColumnId = ic.index_column_id,
ColumnName = col.name,
ind.*,
ic.*,
col.*
FROM
sys.indexes ind
INNER JOIN
sys.i...
How to prevent text in a table cell from wrapping
Does anyone know how I can prevent the text in a table cell from wrapping? This is for the header of a table, and the heading is a lot longer than the data under it, but I need it to display on only one line. It is okay if the column is very wide.
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In SQL, how can you “group by” in ranges?
Suppose I have a table with a numeric column (lets call it "score").
15 Answers
15
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SQL Server: Filter output of sp_who2
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You could try something like
DECLARE @Table TABLE(
SPID INT,
Status VARCHAR(MAX),
LOGIN VARCHAR(MAX),
HostName VARCHAR(MAX),
BlkBy VARCHAR(MAX),
DBName VARCHAR(MAX),
Command VARCHAR(MAX),
CPUTime INT...
How to delete duplicate rows in SQL Server?
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RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1)
FROM dbo.Table1
)
DELETE FROM CTE WHERE RN > 1
DEMO (result is different; I assume that it's due to a typo on your part)
COL1 COL2 COL3 COL4 COL5 COL6 COL7
john 1 1 1 1 1 1
sa...
How to change MySQL column definition?
I have a mySQL table called test:
3 Answers
3
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