Many types of wrestling matches, sometimes called "concept" or "gimmick matches" in the jargon of the business, are performed in professional wrestling.Some of them occur relatively frequently, while others are developed so as to advance an angle, and such match types are used rarely.A constraint is basically a rule associated with a column that the data entered into that column must follow.For example, a "unique" constraint specifies that no two records can have the same value in a particular column. The other two most popular constraints are "not null" which specifies that a column can't be left blank, and "primary key".Data types specify what the type of data can be for that particular column.If a column called "Last_Name", is to be used to hold names, then that particular column should have a "varchar" (variable-length character) data type.Using the same key with a different value changes the value.Example 5-1 declares an associative array that is indexed by a string, populates it, and prints it.
When tables are created, it is common for one or more columns to have constraints associated with them.
Because of professional wrestling's long history over decades, many things have been recycled (many match types often being variations of previous match types).
These match types can be organized into several loose groups.
Playing into this, some storylines have heel champions protect their titles by intentionally losing in such ways.
Some of the most common variations on the singles match restrict the possible means for defeat: only pinfalls are permitted in a Pin only or Pinfall match, only submissions in a Submission match, etc.