![]() It is just that some columns, given the choice, will prefer to use Any column can still store any type of data. The important idea here is that the type is recommended, not The type affinity of a column is the recommended type for data stored In order to maximize compatibility between SQLite and other databaseĮngines, SQLite supports the concept of "type affinity" on columns. INTEGER as Unix Time, the number of seconds sinceĪpplications can choose to store dates and times in any of theseįormats and freely convert between formats using the built-in date.REAL as Julian day numbers, the number of days since.TEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS").Storing dates and times as TEXT, REAL, or INTEGER values: Instead, the built-in Date And Time Functions of SQLite are capable of SQLite does not have a storage class set aside for storing Instead, Boolean values are stored as integers 0 (false) and 1 (true). SQLite does not have a separate Boolean storage class. And so for the most part, "storage class" is indistinguishable from "data type" and the two terms can be used interchangeably. But as soon as INTEGER values are read off of disk and into memory for processing, they are converted to the most general data type (8-byte signed integer). The INTEGER storage class, for example, includes 6 different integer data types of different lengths. Note that a storage class is slightly more general than a data type. The value is a blob of data, stored exactly as it was input. The value is a text string, stored using the database encoding (UTF-8, UTF-16BE or UTF-16LE) The value is a floating point value, stored as an 8-byte IEEE floating point number. The value is a signed integer, stored in 1, 2, 3, 4, 6, or 8 bytes depending on the magnitude of the value. SQLite supports a number of data types in various categories. Sqlite> INSERT INTO t1 VALUES('abcd', '') In SQLite3 (no rigidity) sqlite> CREATE TABLE t1(c1 INTEGER, c2 DATE) Mysql> INSERT INTO t1 VALUES('abcd', '') ĮRROR 1366 (HY000): Incorrect integer value: 'abcd' for column 'c1' at row Test rigid data typing: In MySQL (rigid data types): mysql> CREATE TABLE t1(c1 INTEGER, c2 DATE) 'abcd) in INTEGER type declared column where as SQLite accept the same data in INTEGER type declared column and executes the SELECT statement. Here are two examples where MySQL did not accept a string type data (e.g. Of a value is associated with the value itself, not with its container. integer type always accept integer values) the particular column in which the value is stored. In static typing system, the data type of a value is determined by its container ( e.g. Maximum SQL database engines use static, rigid typing. A data type also specifies the possible values for that type, the operations that can be performed on that type and the way the values of that type are stored.A data type specifies a particular type of data, such as integer, floating-point, Boolean etc.On the other hand, the TEXT, INT, or REAL could be used to store date and time values. Note : SQLite do not have any different storage class for storing dates and/or times. NONE – A column having NONE affinity do not choose one storage class above other and do not change data from one storage class to other.and behaves like a column with NUMERIC affinity. REAL – It forces integer values into floating representation.INTEGER – It has an exception in a CAST expression and behaves in similar way as a column with NUMERIC affinity. ![]()
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