database - a grouping of related information into a single container.  Needs a unique name on the server. Can be up to 64 characters. Cannot start with a space. No forward or backward slashes, exclamation points or asterisks. Spaces are allowed within the name but not recommended.

table - a subset of data within a database, which contains a grouping of similar data items.

data fields - hold individual data elements within a table. This is where the application actually stores the data.

data records - the table groups data fields into data records. Each data record is the information about one occurrence of given set of data fields.

 data type - each data field must be identified as to the type of data that will be stored there.

data constraints - controls how you place data in a data field.

data constraint - primary key -Most popular data constraint is a primary key. MySQL creates a hidden table to relate the primary key values to the records numbers and then retrieves the query data based on the primary key information.

data constrain - IS NULL - If this is present then a value has to be entered into a data field. Primary key cannot have an empty field (this is automatic for all records).



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