Beth, > Sorry....I don't understand. The length is at the front of what?
In some RDBMSs, the VARCHAR data type has a 2 or 4-byte indicator of the length of the stored string before the data itself, while CHAR does not require this information because it is fixed-length. This makes the CHAR datatype marginally smaller, and thus faster, than the VARCHAR data type on those databases. This difference goes back to much older databases and computers, where every byte of a row counted in terms of performance. In my experience, even though MS SQL Server still functions this way, the performance difference between CHAR and VARCHAR is not measurable unless you are getting close to the 8K data page limit that MSSQL imposes. YMMV. Postgres does not materially differentiate between CHAR, VARCHAR, and TEXT, except that CHAR is padded by spaces and VARCHAR often has a length limit. However, in terms of storage efficiency (and indexing efficiency), they are identical. In Postgres, the character count is included in all string data types. Thus, you should use the data type most appropriate to the data you are storing, ignoring performance issues. If the data is a fixed-length string (such as a required zip code) use CHAR; if it's variable but limited, use varchar; if it's a long description, use TEXT. -- -Josh Berkus Aglio Database Solutions San Francisco ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]
