SQL Server the “Lean” wayRandom Thoughts on… DataBloat

Nigel Foulkes-NockFebruary 2016

Confidential

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You don’t always notice it straight away…

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A Table can become very large

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Disk usage by Top Tables

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Examples of Inappropriate DataTypes – page 1 of 2

Integer Datatype

ColumnName Example Datatype Range Bytes Suggestion Bytes

LoanDuration 24 INT +- 2,147,483,648 4SMALLINT 2

PartitionMonth 7INT +- 2,147,483,648 4TINYINT 1

Numeric Datatype

ColumnName Example Datatype Range Bytes Suggestion Bytes

LoanAmount 16000NUMERIC(18,2) precision 10-19 9… (9,2) 5

UnitCost 12999NUMERIC(18,2) precision 10-19 9… (9,2) 5

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Examples of Inappropriate DataTypes – page 2 of 2

Date Datatype

ColumnName Example Datatype Range Bytes Suggestion Bytes

ApplicationDate DateTime1753-01-01 00:00:00.000 - 9999-12-31 00:00:00.000 4SMALL DATETIME 2

DateOfBirth 19991103DateTime1753-01-01 00:00:00.000 - 9999-12-31 00:00:00.000 8DATE 3

Character Datatypes

ColumnName Example Datatype Range Bytes Suggestion Bytes

MonthName January NCHAR(50)A-Z plus Unicode variance values 100VARCHAR(10) 10

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SQL Server is just one large Data cache

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Smaller Data size, less Data CacheingFaster, smarter, more efficient

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Everything becomes more agile - Happy Data, Happy you

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Identifying the Issue – Check your tablessp_help ‘schemaname.tablename’

e.g.

sp_help ‘dbo.TableAdmin’

sp_spaceused ‘schemaname.tablename’

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References

http://www.techrepublic.com/blog/10-things/10-plus-common-questions-about-sql-server-data-types/

http://www.connectionstrings.com/sql-server-data-types-reference/

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http://www.connectionstrings.com/sql-server-data-types-reference/

FIN

Confidential

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Out-takes (removed slide)