SQL Data Types Last Updated : 05 Aug, 2025 Comments Improve Suggest changes Like Article Like Report In SQL, every column in a table must be defined with a data type, which specifies what kind of data it can store such as integers, dates, text or binary values. These types are fundamental to how databases store, retrieve, validate and manipulate data efficiently.Choosing the right data type is critical for maintaining data integrity, improving query performance, and enabling proper indexing and constraints.Each data type ensures:Memory-efficient storageAccurate operations (e.g., arithmetic on numbers, sorting strings)Consistency and validation of input valuesSQL data types are broadly categorized into several groups: 1. Numeric Data TypesNumeric data types are fundamental to database design and are used to store numbers, whether they are integers, decimals or floating-point numbers. These data types allow for mathematical operations like addition, subtraction, multiplication and division, which makes them essential for managing financial, scientific and analytical data.Exact Numeric DatatypeExact numeric types are used when precise numeric values are needed, such as for financial data, quantities, and counts. Some common exact numeric types include:Data TypeDescriptionRangeBIGINTLarge integer numbers-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807INTStandard integer values-2,147,483,648 to 2,147,483,647SMALLINTSmall integers-32,768 to 32,767TINYINTVery small integers0 to 255DECIMALExact fixed-point numbers (e.g., for financial values)-10^38 + 1 to 10^38 - 1NUMERICSimilar to DECIMAL, used for precision data-10^38 + 1 to 10^38 - 1MONEYFor storing monetary values-922,337,203,685,477.5808 to 922,337,203,685,477.5807SMALLMONEYSmaller monetary values-214,748.3648 to 214,748.3647Approximate Numeric DatatypeThese types are used to store approximate values, such as scientific measurements or large ranges of data that don't need exact precision.Data TypeDescriptionRangeFLOATApproximate numeric values-1.79E+308 to 1.79E+308REALSimilar to FLOAT, but with less precision-3.40E+38 to 3.40E+382. Character and String Data TypesCharacter data types are used to store text or character-based data. The choice between fixed-length and variable-length data types depends on the nature of your data.Character String Data TypesData TypeDescriptionCharThe maximum length of 8000 characters. (Fixed-Length non-Unicode Characters)VarcharThe maximum length of 8000 characters. (Variable-Length non-Unicode Characters)Varchar(max)The maximum length of 2^31 - 1 characters(SQL Server 2005 only). (Variable Length non-Unicode data)TextThe maximum length of 2,127,483,647 characters(Variable Length non-Unicode data)Unicode Character String Data TypesUnicode data types are used to store characters from any language, supporting a wider variety of characters. These are given in below table. Data TypeDescriptionNcharThe maximum length of 4000 characters(Fixed-Length Unicode Characters)NvarcharThe maximum length of 4000 characters.(Variable-Length Unicode Characters)Nvarchar(max)The maximum length of 2^31 - 1 characters(SQL Server 2005 only). (Variable Length Unicode data)3. Date and Time Data TypeSQL provides several data types for storing date and time information. They are essential for managing timestamps, events, and time-based queries. These are given in the below table.Data TypeDescriptionStorage SizeDATEstores the data of date (year, month, day)3 BytesTIMEstores the data of time (hour, minute,second)3 BytesDATETIMEstore both the data and time (year, month, day, hour, minute, second)8 Bytes4. Binary Data Types in SQLBinary data types are used to store binary data such as images, videos, or other file types. These include:Data TypeDescriptionMax LengthBinaryFixed-length binary data.8000 bytesVarBinaryVariable-length binary data.8000 bytesImageStores binary data as images.2,147,483,647 bytes5. Boolean Data Type in SQLThe BOOLEAN data types are used to store logical values, typically TRUE or FALSE. It's commonly used for flag fields or binary conditions.6. Special Data TypesSQL also supports some specialized data types for advanced use cases:XML Data Type: Used to store XML data and manipulate XML structures in the databaseSpatial Data Type (Geometry): stores planar spatial data, such as points, lines, and polygons, in a database table. Comment More infoAdvertise with us Next Article What is SQL? S sakshijain1 Follow Improve Article Tags : SQL Databases SQL-basics Similar Reads SQL Tutorial Structured Query Language (SQL) is the standard language used to interact with relational databases. Mainly used to manage data. Whether you want to create, delete, update or read data, SQL provides the structure and commands to perform these operations. Widely supported across various database syst 8 min read BasicsWhat is SQL?Structured Query Language (SQL) is the standard language used to interact with relational databases. Allows users to store, retrieve, update, and manage data efficiently through simple commands. 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