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PostgreSQL Library

The functions listed bellow are for accessing PostgreSQL database.

Function Parameter Type Remark
pgsql([params]) string Creates a PosqgreSQL client object. It also tries to connect to a server if the optional parameter is provided.
.version()   Returns version number as integer.
.connect(params) string Connects to a database server and reports error if failed. The params string may contain any of the following parameters in any order in the form of key=value separated by space character(s): host=host_name, hostaddr=host_IP, port=port_number, dbname=database_name, user=user_name, password=passsword, and connect_timeout=seconds. Refer to the PostgreSQL reference for more details.
.query(sql) string Performs SQL query. Returns an array containing the number of rows the number of columns in the result if successful; otherwise, returns an error string.
.fetch(irow) integer Returns the record of ith row as string or array depending on whether a record has one or more items. It returns null when all records are fetched.
.data(ptr, n) user, integer Fetches all query results, converts them to double floating numbers, and put them into the doubel array ptr of size n. Returns the number of data converted.
.print()   Display query result.
.escape(s) string Create a legal SQL that can be used in an SQL statement.
.escape(ptr, n) user, integer Create a legal SQL string that can be used in an SQL statement. The ptr object must a pointer to binary data of n-bytes.
.unescape(s) string Unescape string to binary data. It returns array containing a pointer to the binary data and the number of byte.
.reset()   Tries to re-connect to the server.

Client Example


sql = pgsql("hostaddr= user=uname password=psw dbname=mydb");

ret = sql.query("SELECT * FROM mytable");

if (isstring(ret)) error(ret);