When the / operator is involved, not only can the result type's precision differ among similar queries, but the result value can differ also. When a query is autoparameterized, the constant value is always converted to numeric (10, 0) before converting to the final data type. For example, the constant value 1 is converted to numeric (1, 0), and the constant value 250 is converted to numeric (3, 0). When a query is not autoparameterized, the constant value is first converted to numeric, whose precision is just large enough to hold the value of the constant, before converting to the specified data type. Therefore, similar expressions in queries can sometimes produce different results. When you use the +, -, *, /, or % arithmetic operators to perform implicit or explicit conversion of int, smallint, tinyint, or bigint constant values to the float, real, decimal or numeric data types, the rules that SQL Server applies when it calculates the data type and precision of the expression results differ depending on whether the query is autoparameterized or not. SQL Server does not automatically promote other integer data types ( tinyint, smallint, and int) to bigint. The bigint data type is intended for use when integer values might exceed the range that is supported by the int data type.īigint fits between smallmoney and int in the data type precedence chart.įunctions return bigint only if the parameter expression is a bigint data type. The int data type is the primary integer data type in SQL Server. But tinyint would not be sufficient for a building's age because a building can be more than 255 years old. For example, tinyint would be sufficient for a person's age because no one lives to be more than 255 years old. To save space in the database, use the smallest data type that can reliably contain all possible values. Scripting on this page enhances content navigation, but does not change the content in any way.Applies to: SQL Server (all supported versions) Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)Įxact-number data types that use integer data. When data is fetched from an analytic workspace to a relational column that has the NUMBER data type, performance is best when the data already has the NUMBER data type in the analytic workspace because a conversion step is not required. When deciding whether to assign the NUMBER data type to a variable, keep the following facts in mind in order to maximize performance:Īnalytic workspace calculations on NUMBER variables is slower than other numerical data types because NUMBER values are calculated in software (for accuracy) rather than in hardware (for speed). It is typically assigned to variables that are not used for calculations (like forecasts and aggregations), and it is used for variables that must match the rounding behavior of the database or require a high degree of precision. It is used for dimensions and surrogates when a text or INTEGER data type is not appropriate. The NUMBER data type is supported by Oracle Database standard libraries and operates the same way as it does in SQL. Positive scale identifies the number of digits to the right of the decimal point negative scale identifies the number of digits to the left of the decimal point that can be rounded up or down. Precision is the number of significant digits. When you define a NUMBER variable, you can specify its precision ( p) and scale ( s) so that it is sufficiently, but not unnecessarily, large. For data display, thousands and decimal markers are controlled by the NLS_NUMERIC_CHARACTERS option as described in "NLS Options". Additionally, a decimal value can contain a decimal point. Note, however, that a comma is required before a negative number that follows another numeric expression, or the minus sign is interpreted as a subtraction operator. Table 2-2 OLAP DML Numeric Data Types Data TypeĪ whole number in the range of (-2**31) to (2**31)-1.Ī whole number in the range of (-2**15) to (2**15)-1.Ī whole number in the range of (-2**63) to (2**63)-1.Ī decimal number with up to 15 significant digits in the range of -(10**308) to +(10**308).Ī decimal number with up to 7 significant digits in the range of -(10**38) to +(10**38).Ī decimal number with up to 38 significant digits in the range of -(10**125) to +(10**125).įor data entry, a value for any of these data types can begin with a plus (+) or minus (-) sign it cannot contain commas.
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